]> www.infradead.org Git - users/dwmw2/linux.git/log
users/dwmw2/linux.git
4 months agox86/mm: Allow temporary MMs when IRQs are on
Andy Lutomirski [Wed, 2 Apr 2025 09:45:38 +0000 (11:45 +0200)]
x86/mm: Allow temporary MMs when IRQs are on

EFI runtime services should use temporary MMs, but EFI runtime services
want IRQs on.  Preemption must still be disabled in a temporary MM context.

At some point, the entirely temporary MM mechanism should be moved out of
arch code.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250402094540.3586683-6-mingo@kernel.org
4 months agox86/mm: Remove 'mm' argument from unuse_temporary_mm() again
Peter Zijlstra [Wed, 2 Apr 2025 09:45:37 +0000 (11:45 +0200)]
x86/mm: Remove 'mm' argument from unuse_temporary_mm() again

Now that unuse_temporary_mm() lives in tlb.c it can access
cpu_tlbstate.loaded_mm.

[ mingo: Merged it on top of x86/alternatives ]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20250402094540.3586683-5-mingo@kernel.org
4 months agox86/mm: Make use_/unuse_temporary_mm() non-static
Andy Lutomirski [Wed, 2 Apr 2025 09:45:36 +0000 (11:45 +0200)]
x86/mm: Make use_/unuse_temporary_mm() non-static

This prepares them for use outside of the alternative machinery.
The code is unchanged.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20250402094540.3586683-4-mingo@kernel.org
4 months agox86/events, x86/insn-eval: Remove incorrect current->active_mm references
Andy Lutomirski [Wed, 2 Apr 2025 09:45:35 +0000 (11:45 +0200)]
x86/events, x86/insn-eval: Remove incorrect current->active_mm references

When decoding an instruction or handling a perf event that references an
LDT segment, if we don't have a valid user context, trying to access the
LDT by any means other than SLDT is racy.  Certainly, using
current->active_mm is wrong, as active_mm can point to a real user mm when
CR3 and LDTR no longer reference that mm.

Clean up the code.  If nmi_uaccess_okay() says we don't have a valid
context, just fail.  Otherwise use current->mm.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20250402094540.3586683-3-mingo@kernel.org
4 months agox86/mm: Add 'mm' argument to unuse_temporary_mm()
Peter Zijlstra [Wed, 2 Apr 2025 09:45:34 +0000 (11:45 +0200)]
x86/mm: Add 'mm' argument to unuse_temporary_mm()

In commit 209954cbc7d0 ("x86/mm/tlb: Update mm_cpumask lazily")
unuse_temporary_mm() grew the assumption that it gets used on
poking_mm exclusively. While this is currently true, lets not hard
code this assumption.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20250402094540.3586683-2-mingo@kernel.org
4 months agox86/alternatives: Make smp_text_poke_batch_process() subsume smp_text_poke_batch_finish()
Nikolay Borisov [Fri, 11 Apr 2025 05:41:05 +0000 (07:41 +0200)]
x86/alternatives: Make smp_text_poke_batch_process() subsume smp_text_poke_batch_finish()

Simplify the alternatives interface some more by moving the
poke_batch_finish check into poke_batch_process and renaming the latter.
The net effect is one less function name to consider when reading the
code.

Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-54-mingo@kernel.org
4 months agox86/alternatives: Add comment about noinstr expectations
Ingo Molnar [Fri, 11 Apr 2025 05:41:04 +0000 (07:41 +0200)]
x86/alternatives: Add comment about noinstr expectations

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-53-mingo@kernel.org
4 months agox86/alternatives: Rename 'apply_relocation()' to 'text_poke_apply_relocation()'
Ingo Molnar [Fri, 11 Apr 2025 05:41:03 +0000 (07:41 +0200)]
x86/alternatives: Rename 'apply_relocation()' to 'text_poke_apply_relocation()'

Join the text_poke_*() API namespace.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-52-mingo@kernel.org
4 months agox86/alternatives: Update the comments in smp_text_poke_batch_process()
Ingo Molnar [Fri, 11 Apr 2025 05:41:02 +0000 (07:41 +0200)]
x86/alternatives: Update the comments in smp_text_poke_batch_process()

 - Capitalize 'INT3' consistently,

 - make it clear that 'sync cores' means an SMP sync to all CPUs,

 - fix typos and spelling.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-51-mingo@kernel.org
4 months agox86/alternatives: Remove 'smp_text_poke_batch_flush()'
Ingo Molnar [Fri, 11 Apr 2025 05:41:01 +0000 (07:41 +0200)]
x86/alternatives: Remove 'smp_text_poke_batch_flush()'

It only has a single user left, merge it into smp_text_poke_batch_add()
and remove the helper function.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-50-mingo@kernel.org
4 months agox86/alternatives: Move declarations of vmlinux.lds.S defined section symbols to ...
Ingo Molnar [Fri, 11 Apr 2025 05:41:00 +0000 (07:41 +0200)]
x86/alternatives: Move declarations of vmlinux.lds.S defined section symbols to <asm/alternative.h>

Move it from the middle of a .c file next to the similar declarations
of __alt_instructions[] et al.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-49-mingo@kernel.org
4 months agox86/alternatives: Simplify the #include section
Ingo Molnar [Fri, 11 Apr 2025 05:40:59 +0000 (07:40 +0200)]
x86/alternatives: Simplify the #include section

We accumulated lots of unnecessary header inclusions over the years,
trim them.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-48-mingo@kernel.org
4 months agox86/alternatives: Rename 'POKE_MAX_OPCODE_SIZE' to 'TEXT_POKE_MAX_OPCODE_SIZE'
Ingo Molnar [Fri, 11 Apr 2025 05:40:58 +0000 (07:40 +0200)]
x86/alternatives: Rename 'POKE_MAX_OPCODE_SIZE' to 'TEXT_POKE_MAX_OPCODE_SIZE'

Join the TEXT_POKE_ namespace.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-47-mingo@kernel.org
4 months agox86/alternatives: Rename 'TP_ARRAY_NR_ENTRIES_MAX' to 'TEXT_POKE_ARRAY_MAX'
Ingo Molnar [Fri, 11 Apr 2025 05:40:57 +0000 (07:40 +0200)]
x86/alternatives: Rename 'TP_ARRAY_NR_ENTRIES_MAX' to 'TEXT_POKE_ARRAY_MAX'

Standardize on TEXT_POKE_ namespace for CPP constants too.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-46-mingo@kernel.org
4 months agox86/alternatives: Standardize on 'tpl' local variable names for 'struct smp_text_poke...
Ingo Molnar [Fri, 11 Apr 2025 05:40:56 +0000 (07:40 +0200)]
x86/alternatives: Standardize on 'tpl' local variable names for 'struct smp_text_poke_loc *'

There's no toilet paper in this code.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-45-mingo@kernel.org
4 months agox86/alternatives: Simplify and clean up patch_cmp()
Ingo Molnar [Fri, 11 Apr 2025 05:40:55 +0000 (07:40 +0200)]
x86/alternatives: Simplify and clean up patch_cmp()

- No need to cast over to 'struct smp_text_poke_loc *', void * is just fine
  for a binary search,

- Use the canonical (a, b) input parameter nomenclature of cmp_func_t
  functions and rename the input parameters from (tp, elt) to
  (tpl_a, tpl_b).

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-44-mingo@kernel.org
4 months agox86/alternatives: Constify text_poke_addr()
Ingo Molnar [Fri, 11 Apr 2025 05:40:54 +0000 (07:40 +0200)]
x86/alternatives: Constify text_poke_addr()

This will also allow the simplification of patch_cmp().

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-43-mingo@kernel.org
4 months agox86/alternatives: Simplify text_poke_addr_ordered()
Ingo Molnar [Fri, 11 Apr 2025 05:40:53 +0000 (07:40 +0200)]
x86/alternatives: Simplify text_poke_addr_ordered()

 - Use direct 'void *' pointer comparison, there's no
   need to force the type to 'unsigned long'.

 - Remove the 'tp' local variable indirection

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-42-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_sync()' to 'smp_text_poke_sync_each_cpu()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:52 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_sync()' to 'smp_text_poke_sync_each_cpu()'

Unlike sync_core(), text_poke_sync() is a very heavy operation, as
it sends an IPI to every online CPU in the system and waits for
completion.

Reflect this in the name.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-41-mingo@kernel.org
4 months agox86/alternatives: Move text_poke_array completion from smp_text_poke_batch_finish...
Ingo Molnar [Fri, 11 Apr 2025 05:40:51 +0000 (07:40 +0200)]
x86/alternatives: Move text_poke_array completion from smp_text_poke_batch_finish() and smp_text_poke_batch_flush() to smp_text_poke_batch_process()

Simplifies the code and improves code generation a bit:

   text    data     bss     dec     hex filename
  14769    1017    4112   19898    4dba alternative.o.before
  14742    1017    4112   19871    4d9f alternative.o.after

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-40-mingo@kernel.org
4 months agox86/alternatives: Add documentation for smp_text_poke_batch_add()
Ingo Molnar [Fri, 11 Apr 2025 05:40:50 +0000 (07:40 +0200)]
x86/alternatives: Add documentation for smp_text_poke_batch_add()

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-39-mingo@kernel.org
4 months agox86/alternatives: Document 'smp_text_poke_single()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:49 +0000 (07:40 +0200)]
x86/alternatives: Document 'smp_text_poke_single()'

Extend the documentation to better describe its purpose.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-38-mingo@kernel.org
4 months agox86/alternatives: Remove the mixed-patching restriction on smp_text_poke_single()
Ingo Molnar [Fri, 11 Apr 2025 05:40:48 +0000 (07:40 +0200)]
x86/alternatives: Remove the mixed-patching restriction on smp_text_poke_single()

At this point smp_text_poke_single(addr, opcode, len, emulate) is equivalent to:

smp_text_poke_batch_add(addr, opcode, len, emulate);
smp_text_poke_batch_finish();

So remove the restriction on mixing single-instruction patching
with multi-instruction patching.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-37-mingo@kernel.org
4 months agox86/alternatives: Move the text_poke_array manipulation into text_poke_int3_loc_init...
Ingo Molnar [Fri, 11 Apr 2025 05:40:47 +0000 (07:40 +0200)]
x86/alternatives: Move the text_poke_array manipulation into text_poke_int3_loc_init() and rename it to __smp_text_poke_batch_add()

This simplifies the code and code generation a bit:

   text    data     bss     dec     hex filename
  14802    1029    4112   19943    4de7 alternative.o.before
  14784    1029    4112   19925    4dd5 alternative.o.after

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-36-mingo@kernel.org
4 months agox86/alternatives: Simplify smp_text_poke_batch_process()
Ingo Molnar [Fri, 11 Apr 2025 05:40:45 +0000 (07:40 +0200)]
x86/alternatives: Simplify smp_text_poke_batch_process()

This function is now using the text_poke_array state exclusively,
make that explicit by removing the redundant input parameters.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-34-mingo@kernel.org
4 months agox86/alternatives: Simplify smp_text_poke_int3_handler()
Ingo Molnar [Fri, 11 Apr 2025 05:40:44 +0000 (07:40 +0200)]
x86/alternatives: Simplify smp_text_poke_int3_handler()

Remove the 'desc' local variable indirection and use
text_poke_array directly.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-33-mingo@kernel.org
4 months agox86/alternatives: Simplify try_get_text_poke_array()
Ingo Molnar [Fri, 11 Apr 2025 05:40:43 +0000 (07:40 +0200)]
x86/alternatives: Simplify try_get_text_poke_array()

There's no need to return a pointer on success - it's always
the same pointer.

Return a bool instead.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-32-mingo@kernel.org
4 months agox86/alternatives: Rename 'put_desc()' to 'put_text_poke_array()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:42 +0000 (07:40 +0200)]
x86/alternatives: Rename 'put_desc()' to 'put_text_poke_array()'

Just like with try_get_text_poke_array(), this name better reflects
what the underlying code is doing, there's no 'descriptor'
indirection anymore.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-31-mingo@kernel.org
4 months agox86/alternatives: Rename 'try_get_desc()' to 'try_get_text_poke_array()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:41 +0000 (07:40 +0200)]
x86/alternatives: Rename 'try_get_desc()' to 'try_get_text_poke_array()'

This better reflects what the underlying code is doing,
there's no 'descriptor' indirection anymore.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-30-mingo@kernel.org
4 months agox86/alternatives: Remove the tp_vec indirection
Ingo Molnar [Fri, 11 Apr 2025 05:40:40 +0000 (07:40 +0200)]
x86/alternatives: Remove the tp_vec indirection

At this point we are always working out of an uptodate
text_poke_array, there's no need for smp_text_poke_int3_handler()
to read via the int3_vec indirection - remove it.

This simplifies the code:

   1 file changed, 5 insertions(+), 15 deletions(-)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-29-mingo@kernel.org
4 months agox86/alternatives: Introduce 'struct smp_text_poke_array' and move tp_vec and tp_vec_n...
Ingo Molnar [Fri, 11 Apr 2025 05:40:39 +0000 (07:40 +0200)]
x86/alternatives: Introduce 'struct smp_text_poke_array' and move tp_vec and tp_vec_nr to it

struct text_poke_array is an equivalent structure to these global variables:

static struct smp_text_poke_loc tp_vec[TP_VEC_MAX];
static int tp_vec_nr;

Note that we intentionally mirror much of the naming of
'struct text_poke_int3_vec', which will further highlight
the unecessary layering going on in this code, and will
ease its removal.

No change in functionality.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-28-mingo@kernel.org
4 months agox86/alternatives: Assert input parameters in smp_text_poke_batch_process()
Ingo Molnar [Fri, 11 Apr 2025 05:40:38 +0000 (07:40 +0200)]
x86/alternatives: Assert input parameters in smp_text_poke_batch_process()

At this point the 'tp' input parameter must always be the
global 'tp_vec' array, and 'nr_entries' must always be equal
to 'tp_vec_nr'.

Assert these conditions - which will allow the removal of
a layer of indirection between these values.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-27-mingo@kernel.org
4 months agox86/alternatives: Assert that smp_text_poke_int3_handler() can only ever handle ...
Ingo Molnar [Fri, 11 Apr 2025 05:40:37 +0000 (07:40 +0200)]
x86/alternatives: Assert that smp_text_poke_int3_handler() can only ever handle 'tp_vec[]' based requests

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-26-mingo@kernel.org
4 months agox86/alternatives: Simplify smp_text_poke_single() by using tp_vec and existing APIs
Ingo Molnar [Fri, 11 Apr 2025 05:40:36 +0000 (07:40 +0200)]
x86/alternatives: Simplify smp_text_poke_single() by using tp_vec and existing APIs

Instead of constructing a vector on-stack, just use the already
available batch-patching vector - which should always be empty
at this point.

This will allow subsequent simplifications.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-25-mingo@kernel.org
4 months agox86/alternatives: Remove the 'addr == NULL means forced-flush' hack from smp_text_pok...
Ingo Molnar [Fri, 11 Apr 2025 05:40:35 +0000 (07:40 +0200)]
x86/alternatives: Remove the 'addr == NULL means forced-flush' hack from smp_text_poke_batch_finish()/smp_text_poke_batch_flush()/text_poke_addr_ordered()

There's this weird hack used by smp_text_poke_batch_finish() to indicate
a 'forced flush':

smp_text_poke_batch_flush(NULL);

Just open-code the vector-flush in a straightforward fashion:

smp_text_poke_batch_process(tp_vec, tp_vec_nr);
tp_vec_nr = 0;

And get rid of !addr hack from text_poke_addr_ordered().

Leave a WARN_ON_ONCE(), just in case some external code learned
to rely on this behavior.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-24-mingo@kernel.org
4 months agox86/alternatives: Use non-inverted logic instead of 'tp_order_fail()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:34 +0000 (07:40 +0200)]
x86/alternatives: Use non-inverted logic instead of 'tp_order_fail()'

tp_order_fail() uses inverted logic: it returns true in case something
is false, which is only a plus at the IOCCC.

Instead rename it to regular parity as 'text_poke_addr_ordered()',
and adjust the code accordingly.

Also add a comment explaining how the address ordering should be
understood.

No change in functionality intended.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-23-mingo@kernel.org
4 months agox86/alternatives: Add text_mutex) assert to smp_text_poke_batch_flush()
Ingo Molnar [Fri, 11 Apr 2025 05:40:33 +0000 (07:40 +0200)]
x86/alternatives: Add text_mutex) assert to smp_text_poke_batch_flush()

It's possible to escape the text_mutex-held assert in
smp_text_poke_batch_process() if the caller uses a properly
batched and sorted series of patch requests, so add
an explicit lockdep_assert_held() to make sure it's
held by all callers.

All text_poke_int3_*() APIs will call either smp_text_poke_batch_process()
or smp_text_poke_batch_flush() internally.

The text_mutex must be held, because tp_vec and tp_vec_nr et al
are all globals, and the INT3 patching machinery itself relies on
external serialization.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-22-mingo@kernel.org
4 months agox86/alternatives: Rename 'int3_desc' to 'int3_vec'
Ingo Molnar [Fri, 11 Apr 2025 05:40:32 +0000 (07:40 +0200)]
x86/alternatives: Rename 'int3_desc' to 'int3_vec'

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-21-mingo@kernel.org
4 months agox86/alternatives: Rename 'struct text_poke_loc' to 'struct smp_text_poke_loc'
Ingo Molnar [Fri, 11 Apr 2025 05:40:30 +0000 (07:40 +0200)]
x86/alternatives: Rename 'struct text_poke_loc' to 'struct smp_text_poke_loc'

Make it clear that this structure is part of the INT3 based
SMP patching facility, not the regular text_poke*() MM-switch
based facility.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-19-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_loc_init()' to 'text_poke_int3_loc_init()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:29 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_loc_init()' to 'text_poke_int3_loc_init()'

This name is actively confusing as well, because the simple text_poke*()
APIs use MM-switching based code patching, while text_poke_loc_init()
is part of the INT3 based text_poke_int3_*() machinery that is an
additional layer of functionality on top of regular text_poke*() functionality.

Rename it to text_poke_int3_loc_init() to make it clear which layer
it belongs to.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-18-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_queue()' to 'smp_text_poke_batch_add()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:28 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_queue()' to 'smp_text_poke_batch_add()'

This name is actively confusing as well, because the simple text_poke*()
APIs use MM-switching based code patching, while text_poke_queue()
is part of the INT3 based text_poke_int3_*() machinery that is an
additional layer of functionality on top of regular text_poke*() functionality.

Rename it to smp_text_poke_batch_add() to make it clear which layer
it belongs to.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-17-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_finish()' to 'smp_text_poke_batch_finish()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:27 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_finish()' to 'smp_text_poke_batch_finish()'

This name is actively confusing as well, because the simple text_poke*()
APIs use MM-switching based code patching, while text_poke_finish()
is part of the INT3 based text_poke_int3_*() machinery that is an
additional layer of functionality on top of regular text_poke*() functionality.

Rename it to smp_text_poke_batch_finish() to make it clear which layer
it belongs to.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-16-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_flush()' to 'smp_text_poke_batch_flush()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:26 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_flush()' to 'smp_text_poke_batch_flush()'

This name is actually actively confusing, because the simple text_poke*()
APIs use MM-switching based code patching, while text_poke_flush()
is part of the INT3 based text_poke_int3_*() machinery that is an
additional layer of functionality on top of regular text_poke*() functionality.

Rename it to smp_text_poke_batch_flush() to make it clear which layer
it belongs to.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-15-mingo@kernel.org
4 months agox86/alternatives: Remove the confusing, inaccurate & unnecessary 'temp_mm_state_t...
Ingo Molnar [Fri, 11 Apr 2025 05:40:25 +0000 (07:40 +0200)]
x86/alternatives: Remove the confusing, inaccurate & unnecessary 'temp_mm_state_t' abstraction

So the temp_mm_state_t abstraction used by use_temporary_mm() and
unuse_temporary_mm() is super confusing:

 - The whole machinery is about temporarily switching to the
   text_poke_mm utility MM that got allocated during bootup
   for text-patching purposes alone:

temp_mm_state_t prev;

        /*
         * Loading the temporary mm behaves as a compiler barrier, which
         * guarantees that the PTE will be set at the time memcpy() is done.
         */
        prev = use_temporary_mm(text_poke_mm);

 - Yet the value that gets saved in the temp_mm_state_t variable
   is not the temporary MM ... but the previous MM...

 - Ie. we temporarily put the non-temporary MM into a variable
   that has the temp_mm_state_t type. This makes no sense whatsoever.

 - The confusion continues in unuse_temporary_mm():

static inline void unuse_temporary_mm(temp_mm_state_t prev_state)

   Here we unuse an MM that is ... not the temporary MM, but the
   previous MM. :-/

Fix up all this confusion by removing the unnecessary layer of
abstraction and using a bog-standard 'struct mm_struct *prev_mm'
variable to save the MM to.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-14-mingo@kernel.org
4 months agox86/alternatives: Update comments in int3_emulate_push()
Ingo Molnar [Fri, 11 Apr 2025 05:40:24 +0000 (07:40 +0200)]
x86/alternatives: Update comments in int3_emulate_push()

The idtentry macro in entry_64.S hasn't had a create_gap
option for 5 years - update the comment.

(Also clean up the entire comment block while at it.)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-13-mingo@kernel.org
4 months agox86/alternatives: Remove duplicate 'text_poke_early()' prototype
Ingo Molnar [Fri, 11 Apr 2025 05:40:23 +0000 (07:40 +0200)]
x86/alternatives: Remove duplicate 'text_poke_early()' prototype

It's declared in <asm/text-patching.h> already.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-12-mingo@kernel.org
4 months agox86/alternatives: Rename 'bp_desc' to 'int3_desc'
Ingo Molnar [Fri, 11 Apr 2025 05:40:22 +0000 (07:40 +0200)]
x86/alternatives: Rename 'bp_desc' to 'int3_desc'

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-11-mingo@kernel.org
4 months agox86/alternatives: Rename 'poking_addr' to 'text_poke_mm_addr'
Ingo Molnar [Fri, 11 Apr 2025 05:40:21 +0000 (07:40 +0200)]
x86/alternatives: Rename 'poking_addr' to 'text_poke_mm_addr'

Put it into the text_poke_* namespace of <asm/text-patching.h>.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-10-mingo@kernel.org
4 months agox86/alternatives: Rename 'poking_mm' to 'text_poke_mm'
Ingo Molnar [Fri, 11 Apr 2025 05:40:20 +0000 (07:40 +0200)]
x86/alternatives: Rename 'poking_mm' to 'text_poke_mm'

Put it into the text_poke_* namespace of <asm/text-patching.h>.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-9-mingo@kernel.org
4 months agox86/alternatives: Rename 'poke_int3_handler()' to 'smp_text_poke_int3_handler()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:19 +0000 (07:40 +0200)]
x86/alternatives: Rename 'poke_int3_handler()' to 'smp_text_poke_int3_handler()'

All related functions in this subsystem already have a
text_poke_int3_ prefix - add it to the trap handler
as well.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-8-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_bp()' to 'smp_text_poke_single()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:18 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_bp()' to 'smp_text_poke_single()'

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-7-mingo@kernel.org
4 months agox86/alternatives: Rename 'text_poke_bp_batch()' to 'smp_text_poke_batch_process()'
Ingo Molnar [Fri, 11 Apr 2025 05:40:17 +0000 (07:40 +0200)]
x86/alternatives: Rename 'text_poke_bp_batch()' to 'smp_text_poke_batch_process()'

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-6-mingo@kernel.org
4 months agox86/alternatives: Rename 'bp_refs' to 'text_poke_array_refs'
Ingo Molnar [Fri, 11 Apr 2025 05:40:16 +0000 (07:40 +0200)]
x86/alternatives: Rename 'bp_refs' to 'text_poke_array_refs'

Make it clear that these reference counts lock access
to text_poke_array.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-5-mingo@kernel.org
4 months agox86/alternatives: Rename 'struct bp_patching_desc' to 'struct text_poke_int3_vec'
Ingo Molnar [Fri, 11 Apr 2025 05:40:15 +0000 (07:40 +0200)]
x86/alternatives: Rename 'struct bp_patching_desc' to 'struct text_poke_int3_vec'

Follow the INT3 text-poking nomenclature, and also adopt the
'vector' name for the entire object, instead of the rather
opaque 'descriptor' naming.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-4-mingo@kernel.org
4 months agox86/alternatives: Document the text_poke_bp_batch() synchronization rules a bit more
Peter Zijlstra [Fri, 11 Apr 2025 05:40:14 +0000 (07:40 +0200)]
x86/alternatives: Document the text_poke_bp_batch() synchronization rules a bit more

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20250411054105.2341982-3-mingo@kernel.org
4 months agox86/alternatives: Improve code-patching scalability by removing false sharing in...
Eric Dumazet [Fri, 11 Apr 2025 05:40:13 +0000 (07:40 +0200)]
x86/alternatives: Improve code-patching scalability by removing false sharing in poke_int3_handler()

eBPF programs can be run 50,000,000 times per second on busy servers.

Whenever /proc/sys/kernel/bpf_stats_enabled is turned off,
hundreds of calls sites are patched from text_poke_bp_batch()
and we see a huge loss of performance due to false sharing
on bp_desc.refs lasting up to three seconds.

   51.30%  server_bin       [kernel.kallsyms]           [k] poke_int3_handler
            |
            |--46.45%--poke_int3_handler
            |          exc_int3
            |          asm_exc_int3
            |          |
            |          |--24.26%--cls_bpf_classify
            |          |          tcf_classify
            |          |          __dev_queue_xmit
            |          |          ip6_finish_output2
            |          |          ip6_output
            |          |          ip6_xmit
            |          |          inet6_csk_xmit
            |          |          __tcp_transmit_skb

Fix this by replacing bp_desc.refs with a per-cpu bp_refs.

Before the patch, on a host with 240 cores (480 threads):

  $ sysctl -wq kernel.bpf_stats_enabled=0

  text_poke_bp_batch(nr_entries=164) : Took 2655300 usec

  $ bpftool prog | grep run_time_ns
  ...
  105: sched_cls  name hn_egress  tag 699fc5eea64144e3  gpl run_time_ns
  3009063719 run_cnt 82757845 : average cost is 36 nsec per call

After this patch:

  $ sysctl -wq kernel.bpf_stats_enabled=0

  text_poke_bp_batch(nr_entries=164) : Took 702 usec

  $ bpftool prog | grep run_time_ns
  ...
  105: sched_cls  name hn_egress  tag 699fc5eea64144e3  gpl run_time_ns
  1928223019 run_cnt 67682728 : average cost is 28 nsec per call

Ie. text-patching performance improved 3700x: from 2.65 seconds
to 0.0007 seconds.

Since the atomic_cond_read_acquire(refs, !VAL) spin-loop was not triggered
even once in my tests, add an unlikely() annotation, because this appears
to be the common case.

[ mingo: Improved the changelog some more. ]

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20250411054105.2341982-2-mingo@kernel.org
4 months agoLinux 6.15-rc1
Linus Torvalds [Sun, 6 Apr 2025 20:11:33 +0000 (13:11 -0700)]
Linux 6.15-rc1

4 months agotools/include: make uapi/linux/types.h usable from assembly
Thomas Weißschuh [Wed, 2 Apr 2025 20:21:57 +0000 (21:21 +0100)]
tools/include: make uapi/linux/types.h usable from assembly

The "real" linux/types.h UAPI header gracefully degrades to a NOOP when
included from assembly code.

Mirror this behaviour in the tools/ variant.

Test for __ASSEMBLER__ over __ASSEMBLY__ as the former is provided by the
toolchain automatically.

Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/lkml/af553c62-ca2f-4956-932c-dd6e3a126f58@sirena.org.uk/
Fixes: c9fbaa879508 ("selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20250321-uapi-consistency-v1-1-439070118dc0@linutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 months agoMerge tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 6 Apr 2025 19:32:43 +0000 (12:32 -0700)]
Merge tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux

Pull turbostat updates from Len Brown:

 - support up to 8192 processors

 - add cpuidle governor debug telemetry, disabled by default

 - update default output to exclude cpuidle invocation counts

 - bug fixes

* tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  tools/power turbostat: v2025.05.06
  tools/power turbostat: disable "cpuidle" invocation counters, by default
  tools/power turbostat: re-factor sysfs code
  tools/power turbostat: Restore GFX sysfs fflush() call
  tools/power turbostat: Document GNR UncMHz domain convention
  tools/power turbostat: report CoreThr per measurement interval
  tools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192
  tools/power turbostat: Add idle governor statistics reporting
  tools/power turbostat: Fix names matching
  tools/power turbostat: Allow Zero return value for some RAPL registers
  tools/power turbostat: Clustered Uncore MHz counters should honor show/hide options

4 months agoMerge tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 6 Apr 2025 19:04:53 +0000 (12:04 -0700)]
Merge tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire

Pull soundwire fix from Vinod Koul:

 - add missing config symbol CONFIG_SND_HDA_EXT_CORE required for asoc
   driver CONFIG_SND_SOF_SOF_HDA_SDW_BPT

* tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire:
  ASoC: SOF: Intel: Let SND_SOF_SOF_HDA_SDW_BPT select SND_HDA_EXT_CORE

4 months agotools/power turbostat: v2025.05.06
Len Brown [Sun, 6 Apr 2025 18:49:20 +0000 (14:49 -0400)]
tools/power turbostat: v2025.05.06

Support up to 8192 processors
Add cpuidle governor debug telemetry, disabled by default
Update default output to exclude cpuidle invocation counts
Bug fixes

Signed-off-by: Len Brown <len.brown@intel.com>
4 months agotools/power turbostat: disable "cpuidle" invocation counters, by default
Len Brown [Sun, 6 Apr 2025 18:29:57 +0000 (14:29 -0400)]
tools/power turbostat: disable "cpuidle" invocation counters, by default

Create "pct_idle" counter group, the sofware notion of residency
so it can now be singled out, independent of other counter groups.

Create "cpuidle" group, the cpuidle invocation counts.
Disable "cpuidle", by default.

Create "swidle" = "cpuidle" + "pct_idle".
Undocument "sysfs", the old name for "swidle", but keep it working
for backwards compatibilty.

Create "hwidle", all the HW idle counters

Modify "idle", enabled by default
"idle" = "hwidle" + "pct_idle" (and now excludes "cpuidle")

Signed-off-by: Len Brown <len.brown@intel.com>
4 months agoMerge tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 6 Apr 2025 17:48:12 +0000 (10:48 -0700)]
Merge tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf event fix from Ingo Molnar:
 "Fix a perf events time accounting bug"

* tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix child_total_time_enabled accounting bug at task exit

4 months agoMerge tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 6 Apr 2025 17:44:58 +0000 (10:44 -0700)]
Merge tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:

 - Fix a nonsensical Kconfig combination

 - Remove an unnecessary rseq-notification

* tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq: Eliminate useless task_work on execve
  sched/isolation: Make CONFIG_CPU_ISOLATION depend on CONFIG_SMP

4 months agoDisable SLUB_TINY for build testing
Linus Torvalds [Sun, 6 Apr 2025 17:00:04 +0000 (10:00 -0700)]
Disable SLUB_TINY for build testing

... and don't error out so hard on missing module descriptions.

Before commit 6c6c1fc09de3 ("modpost: require a MODULE_DESCRIPTION()")
we used to warn about missing module descriptions, but only when
building with extra warnigns (ie 'W=1').

After that commit the warning became an unconditional hard error.

And it turns out not all modules have been converted despite the claims
to the contrary.  As reported by Damian Tometzki, the slub KUnit test
didn't have a module description, and apparently nobody ever really
noticed.

The reason nobody noticed seems to be that the slub KUnit tests get
disabled by SLUB_TINY, which also ends up disabling a lot of other code,
both in tests and in slub itself.  And so anybody doing full build tests
didn't actually see this failre.

So let's disable SLUB_TINY for build-only tests, since it clearly ends
up limiting build coverage.  Also turn the missing module descriptions
error back into a warning, but let's keep it around for non-'W=1'
builds.

Reported-by: Damian Tometzki <damian@riscv-rocks.de>
Link: https://lore.kernel.org/all/01070196099fd059-e8463438-7b1b-4ec8-816d-173874be9966-000000@eu-central-1.amazonses.com/
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Fixes: 6c6c1fc09de3 ("modpost: require a MODULE_DESCRIPTION()")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 months agotools/power turbostat: re-factor sysfs code
Len Brown [Sun, 6 Apr 2025 16:53:18 +0000 (12:53 -0400)]
tools/power turbostat: re-factor sysfs code

Probe cpuidle "sysfs" residency and counts separately,
since soon we will make one disabled on, and the
other disabled off.

Clarify that some BIC (build-in-counters) are actually "groups".
since we're about to re-name some of those groups.

no functional change.

Signed-off-by: Len Brown <len.brown@intel.com>
4 months agotools/power turbostat: Restore GFX sysfs fflush() call
Zhang Rui [Wed, 19 Mar 2025 00:53:07 +0000 (08:53 +0800)]
tools/power turbostat: Restore GFX sysfs fflush() call

Do fflush() to discard the buffered data, before each read of the
graphics sysfs knobs.

Fixes: ba99a4fc8c24 ("tools/power turbostat: Remove unnecessary fflush() call")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
4 months agotools/power turbostat: Document GNR UncMHz domain convention
Len Brown [Sun, 6 Apr 2025 16:23:22 +0000 (12:23 -0400)]
tools/power turbostat: Document GNR UncMHz domain convention

Document that on Intel Granite Rapids Systems,
Uncore domains 0-2 are CPU domains, and
uncore domains 3-4 are IO domains.

Signed-off-by: Len Brown <len.brown@intel.com>
4 months agotools/power turbostat: report CoreThr per measurement interval
Len Brown [Sun, 6 Apr 2025 15:18:39 +0000 (11:18 -0400)]
tools/power turbostat: report CoreThr per measurement interval

The CoreThr column displays total thermal throttling events
since boot time.

Change it to report events during the measurement interval.

This is more useful for showing a user the current conditions.
Total events since boot time are still available to the user via
/sys/devices/system/cpu/cpu*/thermal_throttle/*

Document CoreThr on turbostat.8

Fixes: eae97e053fe30 ("turbostat: Support thermal throttle count print")
Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Chen Yu <yu.c.chen@intel.com>
4 months agotools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192
Justin Ernst [Wed, 19 Mar 2025 20:27:31 +0000 (15:27 -0500)]
tools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192

On systems with >= 1024 cpus (in my case 1152), turbostat fails with the error output:
"turbostat: /sys/fs/cgroup/cpuset.cpus.effective: cpu str malformat 0-1151"

A similar error appears with the use of turbostat --cpu when the inputted cpu
range contains a cpu number >= 1024:
# turbostat -c 1100-1151
"--cpu 1100-1151" malformed
...

Both errors are caused by parse_cpu_str() reaching its limit of CPU_SUBSET_MAXCPUS.

It's a good idea to limit the maximum cpu number being parsed, but 1024 is too low.
For a small increase in compute and allocated memory, increasing CPU_SUBSET_MAXCPUS
brings support for parsing cpu numbers >= 1024.

Increase CPU_SUBSET_MAXCPUS to 8192, a common setting for CONFIG_NR_CPUS on x86_64.

Signed-off-by: Justin Ernst <justin.ernst@hpe.com>
Signed-off-by: Len Brown <len.brown@intel.com>
4 months agoMerge tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 6 Apr 2025 15:35:37 +0000 (08:35 -0700)]
Merge tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer cleanups from Thomas Gleixner:
 "A set of final cleanups for the timer subsystem:

   - Convert all del_timer[_sync]() instances over to the new
     timer_delete[_sync]() API and remove the legacy wrappers.

     Conversion was done with coccinelle plus some manual fixups as
     coccinelle chokes on scoped_guard().

   - The final cleanup of the hrtimer_init() to hrtimer_setup()
     conversion.

     This has been delayed to the end of the merge window, so that all
     patches which have been merged through other trees are in mainline
     and all new users are catched.

  Doing this right before rc1 ensures that new code which is merged post
  rc1 is not introducing new instances of the original functionality"

* tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tracing/timers: Rename the hrtimer_init event to hrtimer_setup
  hrtimers: Rename debug_init_on_stack() to debug_setup_on_stack()
  hrtimers: Rename debug_init() to debug_setup()
  hrtimers: Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper()
  hrtimers: Remove unnecessary NULL check in hrtimer_start_range_ns()
  hrtimers: Make callback function pointer private
  hrtimers: Merge __hrtimer_init() into __hrtimer_setup()
  hrtimers: Switch to use __htimer_setup()
  hrtimers: Delete hrtimer_init()
  treewide: Convert new and leftover hrtimer_init() users
  treewide: Switch/rename to timer_delete[_sync]()

4 months agoMerge tag 'irq-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 6 Apr 2025 15:17:43 +0000 (08:17 -0700)]
Merge tag 'irq-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull more irq updates from Thomas Gleixner:
 "A set of updates for the interrupt subsystem:

   - A treewide cleanup for the irq_domain code, which makes the naming
     consistent and gets rid of the original oddity of naming domains
     'host'.

     This is a trivial mechanical change and is done late to ensure that
     all instances have been catched and new code merged post rc1 wont
     reintroduce new instances.

   - A trivial consistency fix in the migration code

     The recent introduction of irq_force_complete_move() in the core
     code, causes a problem for the nostalgia crowd who maintains ia64
     out of tree.

     The code assumes that hierarchical interrupt domains are enabled
     and dereferences irq_data::parent_data unconditionally. That works
     in mainline because both architectures which enable that code have
     hierarchical domains enabled. Though it breaks the ia64 build,
     which enables the functionality, but does not have hierarchical
     domains.

     While it's not really a problem for mainline today, this
     unconditional dereference is inconsistent and trivially fixable by
     using the existing helper function irqd_get_parent_data(), which
     has the appropriate #ifdeffery in place"

* tag 'irq-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/migration: Use irqd_get_parent_data() in irq_force_complete_move()
  irqdomain: Stop using 'host' for domain
  irqdomain: Rename irq_get_default_host() to irq_get_default_domain()
  irqdomain: Rename irq_set_default_host() to irq_set_default_domain()

4 months agoMerge tag 'timers-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 6 Apr 2025 15:13:16 +0000 (08:13 -0700)]
Merge tag 'timers-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A revert to fix a adjtimex() regression:

  The recent change to prevent that time goes backwards for the coarse
  time getters due to immediate multiplier adjustments via adjtimex(),
  changed the way how the timekeeping core treats that.

  That change result in a regression on the adjtimex() side, which is
  user space visible:

   1) The forwarding of the base time moves the update out of the
      original period and establishes a new one. That's changing the
      behaviour of the [PF]LL control, which user space expects to be
      applied periodically.

   2) The clearing of the accumulated NTP error due to #1, changes the
      behaviour as well.

  An attempt to delay the multiplier/frequency update to the next tick
  did not solve the problem as userspace expects that the multiplier or
  frequency updates are in effect, when the syscall returns.

  There is a different solution for the coarse time problem available,
  so revert the offending commit to restore the existing adjtimex()
  behaviour"

* tag 'timers-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "timekeeping: Fix possible inconsistencies in _COARSE clockids"

4 months agoMerge tag 'sh-for-v6.15-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubi...
Linus Torvalds [Sun, 6 Apr 2025 15:10:45 +0000 (08:10 -0700)]
Merge tag 'sh-for-v6.15-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux

Pull sh updates from John Paul Adrian Glaubitz:
 "One important fix and one small configuration update.

  The first patch by Artur Rojek fixes an issue with the J2 firmware
  loader not being able to find the location of the device tree blob due
  to insufficient alignment of the .bss section which rendered J2 boards
  unbootable.

  The second patch by Johan Korsnes updates the defconfigs on sh to drop
  the CONFIG_NET_CLS_TCINDEX configuration option which became obsolete
  after 8c710f75256b ("net/sched: Retire tcindex classifier").

  Summary:

   - sh: defconfig: Drop obsolete CONFIG_NET_CLS_TCINDEX

   - sh: Align .bss section padding to 8-byte boundary"

* tag 'sh-for-v6.15-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux:
  sh: defconfig: Drop obsolete CONFIG_NET_CLS_TCINDEX
  sh: Align .bss section padding to 8-byte boundary

4 months agoMerge tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy...
Linus Torvalds [Sat, 5 Apr 2025 22:46:50 +0000 (15:46 -0700)]
Merge tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Improve performance in gendwarfksyms

 - Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS

 - Support CONFIG_HEADERS_INSTALL for ARCH=um

 - Use more relative paths to sources files for better reproducibility

 - Support the loong64 Debian architecture

 - Add Kbuild bash completion

 - Introduce intermediate vmlinux.unstripped for architectures that need
   static relocations to be stripped from the final vmlinux

 - Fix versioning in Debian packages for -rc releases

 - Treat missing MODULE_DESCRIPTION() as an error

 - Convert Nios2 Makefiles to use the generic rule for built-in DTB

 - Add debuginfo support to the RPM package

* tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
  kbuild: rpm-pkg: build a debuginfo RPM
  kconfig: merge_config: use an empty file as initfile
  nios2: migrate to the generic rule for built-in DTB
  rust: kbuild: skip `--remap-path-prefix` for `rustdoc`
  kbuild: pacman-pkg: hardcode module installation path
  kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally
  modpost: require a MODULE_DESCRIPTION()
  kbuild: make all file references relative to source root
  x86: drop unnecessary prefix map configuration
  kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS
  kbuild: Add a help message for "headers"
  kbuild: deb-pkg: remove "version" variable in mkdebian
  kbuild: deb-pkg: fix versioning for -rc releases
  Documentation/kbuild: Fix indentation in modules.rst example
  x86: Get rid of Makefile.postlink
  kbuild: Create intermediate vmlinux build with relocations preserved
  kbuild: Introduce Kconfig symbol for linking vmlinux with relocations
  kbuild: link-vmlinux.sh: Make output file name configurable
  kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y
  Revert "kheaders: Ignore silly-rename files"
  ...

4 months agoMerge tag 'drm-next-2025-04-05' of https://gitlab.freedesktop.org/drm/kernel
Linus Torvalds [Sat, 5 Apr 2025 22:35:11 +0000 (15:35 -0700)]
Merge tag 'drm-next-2025-04-05' of https://gitlab.freedesktop.org/drm/kernel

Pull drm fixes from Dave Airlie:
 "Weekly fixes, mostly from the end of last week, this week was very
  quiet, maybe you scared everyone away. It's mostly amdgpu, and xe,
  with some i915, adp and bridge bits, since I think this is overly
  quiet I'd expect rc2 to be a bit more lively.

  bridge:
   - tda998x: Select CONFIG_DRM_KMS_HELPER

  amdgpu:
   - Guard against potential division by 0 in fan code
   - Zero RPM support for SMU 14.0.2
   - Properly handle SI and CIK support being disabled
   - PSR fixes
   - DML2 fixes
   - DP Link training fix
   - Vblank fixes
   - RAS fixes
   - Partitioning fix
   - SDMA fix
   - SMU 13.0.x fixes
   - Rom fetching fix
   - MES fixes
   - Queue reset fix

  xe:
   - Fix NULL pointer dereference on error path
   - Add missing HW workaround for BMG
   - Fix survivability mode not triggering
   - Fix build warning when DRM_FBDEV_EMULATION is not set

  i915:
   - Bounds check for scalers in DSC prefill latency computation
   - Fix build by adding a missing include

  adp:
   - Fix error handling in plane setup"

  # -----BEGIN PGP SIGNATURE-----

* tag 'drm-next-2025-04-05' of https://gitlab.freedesktop.org/drm/kernel: (34 commits)
  drm/i2c: tda998x: select CONFIG_DRM_KMS_HELPER
  drm/amdgpu/gfx12: fix num_mec
  drm/amdgpu/gfx11: fix num_mec
  drm/amd/pm: Add gpu_metrics_v1_8
  drm/amdgpu: Prefer shadow rom when available
  drm/amd/pm: Update smu metrics table for smu_v13_0_6
  drm/amd/pm: Remove host limit metrics support
  Remove unnecessary firmware version check for gc v9_4_2
  drm/amdgpu: stop unmapping MQD for kernel queues v3
  Revert "drm/amdgpu/sdma_v4_4_2: update VM flush implementation for SDMA"
  drm/amdgpu: Parse all deferred errors with UMC aca handle
  drm/amdgpu: Update ta ras block
  drm/amdgpu: Add NPS2 to DPX compatible mode
  drm/amdgpu: Use correct gfx deferred error count
  drm/amd/display: Actually do immediate vblank disable
  drm/amd/display: prevent hang on link training fail
  Revert "drm/amd/display: dml2 soc dscclk use DPM table clk setting"
  drm/amd/display: Increase vblank offdelay for PSR panels
  drm/amd: Handle being compiled without SI or CIK support better
  drm/amd/pm: Add zero RPM enabled OD setting support for SMU14.0.2
  ...

4 months agokbuild: rpm-pkg: build a debuginfo RPM
Uday Shankar [Mon, 31 Mar 2025 22:46:32 +0000 (16:46 -0600)]
kbuild: rpm-pkg: build a debuginfo RPM

The rpm-pkg make target currently suffers from a few issues related to
debuginfo:
1. debuginfo for things built into the kernel (vmlinux) is not available
   in any RPM produced by make rpm-pkg. This makes using tools like
   systemtap against a make rpm-pkg kernel impossible.
2. debug source for the kernel is not available. This means that
   commands like 'disas /s' in gdb, which display source intermixed with
   assembly, can only print file names/line numbers which then must be
   painstakingly resolved to actual source in a separate editor.
3. debuginfo for modules is available, but it remains bundled with the
   .ko files that contain module code, in the main kernel RPM. This is a
   waste of space for users who do not need to debug the kernel (i.e.
   most users).

Address all of these issues by additionally building a debuginfo RPM
when the kernel configuration allows for it, in line with standard
patterns followed by RPM distributors. With these changes:
1. systemtap now works (when these changes are backported to 6.11, since
   systemtap lags a bit behind in compatibility), as verified by the
   following simple test script:

   # stap -e 'probe kernel.function("do_sys_open").call { printf("%s\n", $$parms); }'
   dfd=0xffffffffffffff9c filename=0x7fe18800b160 flags=0x88800 mode=0x0
   ...

2. disas /s works correctly in gdb, with source and disassembly
   interspersed:

   # gdb vmlinux --batch -ex 'disas /s blk_op_str'
   Dump of assembler code for function blk_op_str:
   block/blk-core.c:
   125     {
      0xffffffff814c8740 <+0>:     endbr64

   127
   128             if (op < ARRAY_SIZE(blk_op_name) && blk_op_name[op])
      0xffffffff814c8744 <+4>:     mov    $0xffffffff824a7378,%rax
      0xffffffff814c874b <+11>:    cmp    $0x23,%edi
      0xffffffff814c874e <+14>:    ja     0xffffffff814c8768 <blk_op_str+40>
      0xffffffff814c8750 <+16>:    mov    %edi,%edi

   126             const char *op_str = "UNKNOWN";
      0xffffffff814c8752 <+18>:    mov    $0xffffffff824a7378,%rdx

   127
   128             if (op < ARRAY_SIZE(blk_op_name) && blk_op_name[op])
      0xffffffff814c8759 <+25>:    mov    -0x7dfa0160(,%rdi,8),%rax

   126             const char *op_str = "UNKNOWN";
      0xffffffff814c8761 <+33>:    test   %rax,%rax
      0xffffffff814c8764 <+36>:    cmove  %rdx,%rax

   129                     op_str = blk_op_name[op];
   130
   131             return op_str;
   132     }
      0xffffffff814c8768 <+40>:    jmp    0xffffffff81d01360 <__x86_return_thunk>
   End of assembler dump.

3. The size of the main kernel package goes down substantially,
   especially if many modules are built (quite typical). Here is a
   comparison of installed size of the kernel package (configured with
   allmodconfig, dwarf4 debuginfo, and module compression turned off)
   before and after this patch:

   # rpm -qi kernel-6.13* | grep -E '^(Version|Size)'
   Version     : 6.13.0postpatch+
   Size        : 1382874089
   Version     : 6.13.0prepatch+
   Size        : 17870795887

   This is a ~92% size reduction.

Note that a debuginfo package can only be produced if the following
configs are set:
- CONFIG_DEBUG_INFO=y
- CONFIG_MODULE_COMPRESS=n
- CONFIG_DEBUG_INFO_SPLIT=n

The first of these is obvious - we can't produce debuginfo if the build
does not generate it. The second two requirements can in principle be
removed, but doing so is difficult with the current approach, which uses
a generic rpmbuild script find-debuginfo.sh that processes all packaged
executables. If we want to remove those requirements the best path
forward is likely to add some debuginfo extraction/installation logic to
the modules_install target (controllable by flags). That way, it's
easier to operate on modules before they're compressed, and the logic
can be reused by all packaging targets.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 months agokconfig: merge_config: use an empty file as initfile
Daniel Gomez [Fri, 28 Mar 2025 14:28:37 +0000 (14:28 +0000)]
kconfig: merge_config: use an empty file as initfile

The scripts/kconfig/merge_config.sh script requires an existing
$INITFILE (or the $1 argument) as a base file for merging Kconfig
fragments. However, an empty $INITFILE can serve as an initial starting
point, later referenced by the KCONFIG_ALLCONFIG Makefile variable
if -m is not used. This variable can point to any configuration file
containing preset config symbols (the merged output) as stated in
Documentation/kbuild/kconfig.rst. When -m is used $INITFILE will
contain just the merge output requiring the user to run make (i.e.
KCONFIG_ALLCONFIG=<$INITFILE> make <allnoconfig/alldefconfig> or make
olddefconfig).

Instead of failing when `$INITFILE` is missing, create an empty file and
use it as the starting point for merges.

Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 months agonios2: migrate to the generic rule for built-in DTB
Masahiro Yamada [Sun, 22 Dec 2024 00:30:53 +0000 (09:30 +0900)]
nios2: migrate to the generic rule for built-in DTB

Commit 654102df2ac2 ("kbuild: add generic support for built-in boot
DTBs") introduced generic support for built-in DTBs.

Select GENERIC_BUILTIN_DTB when built-in DTB support is enabled.

To keep consistency across architectures, this commit also renames
CONFIG_NIOS2_DTB_SOURCE_BOOL to CONFIG_BUILTIN_DTB, and
CONFIG_NIOS2_DTB_SOURCE to CONFIG_BUILTIN_DTB_NAME.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 months agosh: defconfig: Drop obsolete CONFIG_NET_CLS_TCINDEX
Johan Korsnes [Sun, 23 Mar 2025 19:13:30 +0000 (20:13 +0100)]
sh: defconfig: Drop obsolete CONFIG_NET_CLS_TCINDEX

This option was removed from Kconfig in 8c710f75256b ("net/sched:
Retire tcindex classifier") but from the defconfigs.

Fixes: 8c710f75256b ("net/sched: Retire tcindex classifier")
Signed-off-by: Johan Korsnes <johan.korsnes@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
4 months agosh: Align .bss section padding to 8-byte boundary
Artur Rojek [Sun, 16 Feb 2025 17:55:44 +0000 (18:55 +0100)]
sh: Align .bss section padding to 8-byte boundary

J2-based devices expect to find a device tree blob at the end of the
.bss section. As of a77725a9a3c5 ("scripts/dtc: Update to upstream
version v1.6.1-19-g0a3a9d3449c8"), libfdt enforces 8-byte alignment
for the DTB, causing J2 devices to fail early in sh_fdt_init().

As the J2 loader firmware calculates the DTB location based on the kernel
image .bss section size rather than the __bss_stop symbol offset, the
required alignment can't be enforced with BSS_SECTION(0, PAGE_SIZE, 8).

To fix this, inline a modified version of the above macro which grows
.bss by the required size. While this change affects all existing SH
boards, it should be benign on platforms which don't need this alignment.

Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: Rob Landley <rob@landley.net>
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
4 months agoMerge tag 'input-for-v6.15-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sat, 5 Apr 2025 16:20:39 +0000 (09:20 -0700)]
Merge tag 'input-for-v6.15-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

Pull input updates from Dmitry Torokhov:

 - a brand new driver for touchpads and touchbars in newer Apple devices

 - support for Berlin-A series in goodix-berlin touchscreen driver

 - improvements to matrix_keypad driver to better handle GPIOs toggling

 - assorted small cleanups in other input drivers

* tag 'input-for-v6.15-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: goodix_berlin - add support for Berlin-A series
  dt-bindings: input: goodix,gt9916: Document gt9897 compatible
  dt-bindings: input: matrix_keypad - add wakeup-source property
  dt-bindings: input: matrix_keypad - add missing property
  Input: pm8941-pwrkey - fix dev_dbg() output in pm8941_pwrkey_irq()
  Input: synaptics - hide unused smbus_pnp_ids[] array
  Input: apple_z2 - fix potential confusion in Kconfig
  Input: matrix_keypad - use fsleep for delays after activating columns
  Input: matrix_keypad - add settle time after enabling all columns
  dt-bindings: input: matrix_keypad: add settle time after enabling all columns
  dt-bindings: input: matrix_keypad: convert to YAML
  dt-bindings: input: Correct indentation and style in DTS example
  MAINTAINERS: Add entries for Apple Z2 touchscreen driver
  Input: apple_z2 - add a driver for Apple Z2 touchscreens
  dt-bindings: input: touchscreen: Add Z2 controller
  Input: Switch to use hrtimer_setup()
  Input: drop vb2_ops_wait_prepare/finish

4 months agotracing/timers: Rename the hrtimer_init event to hrtimer_setup
Nam Cao [Wed, 5 Feb 2025 10:55:21 +0000 (11:55 +0100)]
tracing/timers: Rename the hrtimer_init event to hrtimer_setup

The function hrtimer_init() doesn't exist anymore. It was replaced by
hrtimer_setup().

Thus, rename the hrtimer_init trace event to hrtimer_setup to keep it
consistent.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/cba84c3d853c5258aa3a262363a6eac08e2c7afc.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Rename debug_init_on_stack() to debug_setup_on_stack()
Nam Cao [Wed, 5 Feb 2025 10:55:20 +0000 (11:55 +0100)]
hrtimers: Rename debug_init_on_stack() to debug_setup_on_stack()

All the hrtimer_init*() functions have been renamed to hrtimer_setup*().
Rename debug_init_on_stack() to debug_setup_on_stack() as well, to keep the
names consistent.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/073cf6162779a2f5b12624677d4c49ee7eccc1ed.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Rename debug_init() to debug_setup()
Nam Cao [Wed, 5 Feb 2025 10:55:19 +0000 (11:55 +0100)]
hrtimers: Rename debug_init() to debug_setup()

All the hrtimer_init*() functions have been renamed to hrtimer_setup*().
Rename debug_init() to debug_setup() as well, to keep the names consistent.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/4b730c1f79648b16a1c5413f928fdc2e138dfc43.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper()
Nam Cao [Wed, 5 Feb 2025 10:55:18 +0000 (11:55 +0100)]
hrtimers: Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper()

All the hrtimer_init*() functions have been renamed to hrtimer_setup*().
Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper() as well, to
keep the names consistent.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/807694aedad9353421c4a7347629a30c5c31026f.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Remove unnecessary NULL check in hrtimer_start_range_ns()
Nam Cao [Wed, 5 Feb 2025 10:55:17 +0000 (11:55 +0100)]
hrtimers: Remove unnecessary NULL check in hrtimer_start_range_ns()

The struct hrtimer::function field can only be changed using
hrtimer_setup*() or hrtimer_update_function(), and both already null-check
'function'. Therefore, null-checking 'function' in hrtimer_start_range_ns()
is not necessary.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/4661c571ee87980c340ccc318fc1a473c0c8f6bc.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Make callback function pointer private
Nam Cao [Wed, 5 Feb 2025 10:55:16 +0000 (11:55 +0100)]
hrtimers: Make callback function pointer private

Make the struct hrtimer::function field private, to prevent users from
changing this field in an unsafe way. hrtimer_update_function() should be
used if the callback function needs to be changed.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/7d0e6e0c5c59a64a9bea940051aac05d750bc0c2.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Merge __hrtimer_init() into __hrtimer_setup()
Nam Cao [Wed, 5 Feb 2025 10:55:12 +0000 (11:55 +0100)]
hrtimers: Merge __hrtimer_init() into __hrtimer_setup()

__hrtimer_init() is only called by __hrtimer_setup(). Simplify by merging
__hrtimer_init() into __hrtimer_setup().

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/8a0a847a35f711f66b2d05b57255aa44e7e61279.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Switch to use __htimer_setup()
Nam Cao [Wed, 5 Feb 2025 10:55:11 +0000 (11:55 +0100)]
hrtimers: Switch to use __htimer_setup()

__hrtimer_init_sleeper() calls __hrtimer_init() and also sets up the
callback function. But there is already __hrtimer_setup() which does both
actions.

Switch to use __hrtimer_setup() to simplify the code.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/d9a45a51b6a8aa0045310d63f73753bf6b33f385.1738746927.git.namcao@linutronix.de
4 months agohrtimers: Delete hrtimer_init()
Nam Cao [Wed, 5 Feb 2025 10:55:10 +0000 (11:55 +0100)]
hrtimers: Delete hrtimer_init()

hrtimer_init() is now unused. Delete it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/003722f60c7a2a4f8d4ed24fb741aa313b7e5136.1738746927.git.namcao@linutronix.de
4 months agotreewide: Convert new and leftover hrtimer_init() users
Thomas Gleixner [Fri, 4 Apr 2025 17:31:15 +0000 (19:31 +0200)]
treewide: Convert new and leftover hrtimer_init() users

hrtimer_setup() takes the callback function pointer as argument and
initializes the timer completely.

Replace hrtimer_init() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Coccinelle scripted cleanup.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
4 months agotreewide: Switch/rename to timer_delete[_sync]()
Thomas Gleixner [Sat, 5 Apr 2025 08:17:26 +0000 (10:17 +0200)]
treewide: Switch/rename to timer_delete[_sync]()

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
4 months agoMerge branch 'next' into for-linus
Dmitry Torokhov [Sat, 5 Apr 2025 06:04:35 +0000 (23:04 -0700)]
Merge branch 'next' into for-linus

Prepare input updates for 6.15 merge window.

4 months agoMerge tag 'v6.15-p3' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Linus Torvalds [Sat, 5 Apr 2025 02:34:38 +0000 (19:34 -0700)]
Merge tag 'v6.15-p3' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto fix from Herbert Xu:
 "This fixes a race condition in the newly added eip93 driver"

* tag 'v6.15-p3' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: inside-secure/eip93 - acquire lock on eip93_put_descriptor hash

4 months agoMerge tag 's390-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Linus Torvalds [Fri, 4 Apr 2025 23:58:34 +0000 (16:58 -0700)]
Merge tag 's390-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Vasily Gorbik:

 - Fix machine check handler _CIF_MCCK_GUEST bit setting by adding the
   missing base register for relocated lowcore address

 - Fix build failure on older linkers by conditionally adding the
   -no-pie linker option only when it is supported

 - Fix inaccurate kernel messages in vfio-ap by providing descriptive
   error notifications for AP queue sharing violations

 - Fix PCI isolation logic by ensuring non-VF devices correctly return
   false in zpci_bus_is_isolated_vf()

 - Fix PCI DMA range map setup by using dma_direct_set_offset() to add a
   proper sentinel element, preventing potential overruns and
   translation errors

 - Cleanup header dependency problems with asm-offsets.c

 - Add fault info for unexpected low-address protection faults in user
   mode

 - Add support for HOTPLUG_SMT, replacing the arch-specific "nosmt"
   handling with common code handling

 - Use bitop functions to implement CPU flag helper functions to ensure
   that bits cannot get lost if modified in different contexts on a CPU

 - Remove unused machine_flags for the lowcore

* tag 's390-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/vfio-ap: Fix no AP queue sharing allowed message written to kernel log
  s390/pci: Fix dev.dma_range_map missing sentinel element
  s390/mm: Dump fault info in case of low address protection fault
  s390/smp: Add support for HOTPLUG_SMT
  s390: Fix linker error when -no-pie option is unavailable
  s390/processor: Use bitop functions for cpu flag helper functions
  s390/asm-offsets: Remove ASM_OFFSETS_C
  s390/asm-offsets: Include ftrace_regs.h instead of ftrace.h
  s390/kvm: Split kvm_host header file
  s390/pci: Fix zpci_bus_is_isolated_vf() for non-VFs
  s390/lowcore: Remove unused machine_flags
  s390/entry: Fix setting _CIF_MCCK_GUEST with lowcore relocation

4 months agoMerge tag '6.15-rc-part2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Linus Torvalds [Fri, 4 Apr 2025 22:27:43 +0000 (15:27 -0700)]
Merge tag '6.15-rc-part2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull more smb client updates from Steve French:

 - reconnect fixes: three for updating rsize/wsize and an SMB1 reconnect
   fix

 - RFC1001 fixes: fixing connections to nonstandard ports, and negprot
   retries

 - fix mfsymlinks to old servers

 - make mapping of open flags for SMB1 more accurate

 - permission fixes: adding retry on open for write, and one for stat to
   workaround unexpected access denied

 - add two new xattrs, one for retrieving SACL and one for retrieving
   owner (without having to retrieve the whole ACL)

 - fix mount parm validation for echo_interval

 - minor cleanup (including removing now unneeded cifs_truncate_page)

* tag '6.15-rc-part2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: update internal version number
  cifs: Implement is_network_name_deleted for SMB1
  cifs: Remove cifs_truncate_page() as it should be superfluous
  cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL
  cifs: Improve SMB2+ stat() to work also without FILE_READ_ATTRIBUTES
  cifs: Add fallback for SMB2 CREATE without FILE_READ_ATTRIBUTES
  cifs: Fix querying and creating MF symlinks over SMB1
  cifs: Fix access_flags_to_smbopen_mode
  cifs: Fix negotiate retry functionality
  cifs: Improve handling of NetBIOS packets
  cifs: Allow to disable or force initialization of NetBIOS session
  cifs: Add a new xattr system.smb3_ntsd_owner for getting or setting owner
  cifs: Add a new xattr system.smb3_ntsd_sacl for getting or setting SACLs
  smb: client: Update IO sizes after reconnection
  smb: client: Store original IO parameters and prevent zero IO sizes
  smb:client: smb: client: Add reverse mapping from tcon to superblocks
  cifs: remove unreachable code in cifs_get_tcp_session()
  cifs: fix integer overflow in match_server()

4 months agoMerge tag 'ntb-6.15' of https://github.com/jonmason/ntb
Linus Torvalds [Fri, 4 Apr 2025 21:23:07 +0000 (14:23 -0700)]
Merge tag 'ntb-6.15' of https://github.com/jonmason/ntb

Pull ntb fixes from Jon Mason:
 "Bug fixes for NTB Switchtec driver mw negative shift, Intel NTB link
  status db, ntb_perf double unmap (in error case), and MSI 64bit
  arithmetic.

  Also, add new AMD NTB PCI IDs, update AMD NTB maintainer, and pull in
  patch to reduce the stack usage in IDT driver"

* tag 'ntb-6.15' of https://github.com/jonmason/ntb:
  ntb_hw_amd: Add NTB PCI ID for new gen CPU
  ntb: reduce stack usage in idt_scan_mws
  ntb: use 64-bit arithmetic for the MSI doorbell mask
  MAINTAINERS: Update AMD NTB maintainers
  ntb_perf: Delete duplicate dmaengine_unmap_put() call in perf_copy_chunk()
  ntb: intel: Fix using link status DB's
  ntb_hw_switchtec: Fix shift-out-of-bounds in switchtec_ntb_mw_set_trans

4 months agoMerge tag 'drm-misc-next-fixes-2025-04-04' of https://gitlab.freedesktop.org/drm...
Dave Airlie [Fri, 4 Apr 2025 20:27:56 +0000 (06:27 +1000)]
Merge tag 'drm-misc-next-fixes-2025-04-04' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-next

Short summary of fixes pull:

bridge:
- tda998x: Select CONFIG_DRM_KMS_HELPER

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250404065105.GA27699@linux.fritz.box
4 months agoRevert "timekeeping: Fix possible inconsistencies in _COARSE clockids"
Thomas Gleixner [Fri, 4 Apr 2025 15:10:52 +0000 (17:10 +0200)]
Revert "timekeeping: Fix possible inconsistencies in _COARSE clockids"

This reverts commit 757b000f7b936edf79311ab0971fe465bbda75ea.

Miroslav reported that the changes for handling the inconsistencies in the
coarse time getters result in a regression on the adjtimex() side.

There are two issues:

  1) The forwarding of the base time moves the update out of the original
     period and establishes a new one.

  2) The clearing of the accumulated NTP error is changing the behaviour as
     well.

Userspace expects that multiplier/frequency updates are in effect, when the
syscall returns, so delaying the update to the next tick is not solving the
problem either.

Revert the change, so that the established expectations of user space
implementations (ntpd, chronyd) are restored. The re-introduced
inconsistency of the coarse time getters will be addressed in a subsequent
fix.

Fixes: 757b000f7b93 ("timekeeping: Fix possible inconsistencies in _COARSE clockids")
Reported-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/Z-qsg6iDGlcIJulJ@localhost