Rob Herring [Wed, 14 Jun 2023 17:17:23 +0000 (11:17 -0600)]
powerpc: 52xx: Make immr_id DT match tables static
In some builds, the mpc52xx_pm_prepare()/lite5200_pm_prepare() functions
generate stack size warnings. The addition of 'struct resource' in commit 2500763dd3db ("powerpc: Use of_address_to_resource()") grew the stack size
and is blamed for the warnings. However, the real issue is there's no
reason the 'struct of_device_id immr_ids' DT match tables need to be on
the stack as they are constant. Declare them as static to move them off
the stack.
Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202306130405.uTv5yOZD-lkp@intel.com/ Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230614171724.2403982-1-robh@kernel.org
Rob Herring [Fri, 9 Jun 2023 18:32:38 +0000 (12:32 -0600)]
powerpc: fsl_soc: Use of_range_to_resource() for "ranges" parsing
"ranges" is a standard property with common parsing functions. Users
shouldn't be implementing their own parsing of it. Refactor the FSL RapidIO
"ranges" parsing to use of_range_to_resource() instead.
Rob Herring [Fri, 9 Jun 2023 18:32:44 +0000 (12:32 -0600)]
powerpc: fsl_rio: Use of_range_to_resource() for "ranges" parsing
"ranges" is a standard property with common parsing functions. Users
shouldn't be implementing their own parsing of it. Refactor the FSL RapidIO
"ranges" parsing to use of_range_to_resource() instead.
One change is the original code would look for "#size-cells" and
"#address-cells" in the parent node if not found in the port child
nodes. That is non-standard behavior and not necessary AFAICT. In 2011
in commit 54986964c13c ("powerpc/85xx: Update SRIO device tree nodes")
there was an ABI break. The upstream .dts files have been correct since
at least that point.
Signed-off-by: Rob Herring <robh@kernel.org>
[mpe: Remove now unused "cell" variable] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230609183244.1767325-1-robh@kernel.org
"ranges" is a standard property with common parsing functions. Users
shouldn't be implementing their own parsing of it. Refactor the FSL RapidIO
"ranges" parsing to use of_range_to_resource() instead.
One change is the original code would look for "#size-cells" and
"#address-cells" in the parent node if not found in the port child
nodes. That is non-standard behavior and not necessary AFAICT. In 2011
in commit 54986964c13c ("powerpc/85xx: Update SRIO device tree nodes")
there was an ABI break. The upstream .dts files have been correct since
at least that point.
Paul Gortmaker [Tue, 20 Jun 2023 04:33:00 +0000 (00:33 -0400)]
powerpc: drop MPC85xx_CDS platform support
The MPC8541/8548/8555 Configurable Development System (CDS) were the
vehicle used to provide evaluation of the 1st e500-v2 CPUs around 2007.
Similar to the earlier MPC83xx-MDS systems we removed, the "brains"
exist on a PCI-X card, but additional connectors exist to the right of
the PCI-X slot, two structural metal pins are used to provide stability
in a vertical ATX mounting, and the CPU is now on a daughter-card vs. a
clamped down BGA.
Given the extra complexity and risk of connector damage, the 8548CDS
I had access to came pre-assembled in a basic white Antec case common
for that era, and I'm inclined to assume that was the default.
Power was typical "Pentium4" 2005 ATX - the main 20 pin connector went
to the PCI ATX form factor backplane, and the 4 pin black/yellow went
to the CPU card.
Like previous evaluation boards, they attempted to provide break-out
connectors for as many features as possible, and that made for a fairly
complex looking system.
In any case, these are over 15 years old, and fairly complex systems,
originally made for a small group of industry related people, and made
for use where quiet fan operation wasn't important. Given that, it
makes sense to remove support from them in 2023.
Paul Gortmaker [Tue, 20 Jun 2023 04:32:59 +0000 (00:32 -0400)]
powerpc: drop MPC8540_ADS and MPC8560_ADS platform support
Based on the revision history in the manual(s), these e500-v1
platforms were first available around 2002.
Like a lot of evaluation boards, they attempted to provide break-out
connectors for all possible features, and that combined with four
PCI-X slots (and the age/era) meant for a considerably large board.
As I recall it, from a Linux point of view, the biggest difference
between 8540 and 8560 was in the UART implementation, and that is
reflected in a diff of the defconfigs.
In any case, these are over 20 years old, and by today's standards
only have a small amount of DDR1 memory, and were not widely available.
Given that, it makes sense to remove support from them in 2023.
powerpc/mm/dax: Fix the condition when checking if altmap vmemap can cross-boundary
Without this fix, the last subsection vmemmap can end up in memory even if
the namespace is created with -M mem and has sufficient space in the altmap
area.
Fixes: cf387d9644d8 ("libnvdimm/altmap: Track namespace boundaries in altmap") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com <mailto:sachinp@linux.ibm.com>> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230616110826.344417-6-aneesh.kumar@linux.ibm.com
Aditya Gupta [Thu, 15 Jun 2023 09:10:47 +0000 (14:40 +0530)]
powerpc: update ppc_save_regs to save current r1 in pt_regs
ppc_save_regs() skips one stack frame while saving the CPU register states.
Instead of saving current R1, it pulls the previous stack frame pointer.
When vmcores caused by direct panic call (such as `echo c >
/proc/sysrq-trigger`), are debugged with gdb, gdb fails to show the
backtrace correctly. On further analysis, it was found that it was because
of mismatch between r1 and NIP.
GDB uses NIP to get current function symbol and uses corresponding debug
info of that function to unwind previous frames, but due to the
mismatching r1 and NIP, the unwinding does not work, and it fails to
unwind to the 2nd frame and hence does not show the backtrace.
GDB backtrace with vmcore of kernel without this patch:
---------
(gdb) bt
#0 0xc0000000002a53e8 in crash_setup_regs (oldregs=<optimized out>,
newregs=0xc000000004f8f8d8) at ./arch/powerpc/include/asm/kexec.h:69
#1 __crash_kexec (regs=<optimized out>) at kernel/kexec_core.c:974
#2 0x0000000000000063 in ?? ()
#3 0xc000000003579320 in ?? ()
---------
Further analysis revealed that the mismatch occurred because
"ppc_save_regs" was saving the previous stack's SP instead of the current
r1. This patch fixes this by storing current r1 in the saved pt_regs.
GDB backtrace with vmcore of patched kernel:
--------
(gdb) bt
#0 0xc0000000002a53e8 in crash_setup_regs (oldregs=0x0, newregs=0xc00000000670b8d8)
at ./arch/powerpc/include/asm/kexec.h:69
#1 __crash_kexec (regs=regs@entry=0x0) at kernel/kexec_core.c:974
#2 0xc000000000168918 in panic (fmt=fmt@entry=0xc000000001654a60 "sysrq triggered crash\n")
at kernel/panic.c:358
#3 0xc000000000b735f8 in sysrq_handle_crash (key=<optimized out>) at drivers/tty/sysrq.c:155
#4 0xc000000000b742cc in __handle_sysrq (key=key@entry=99, check_mask=check_mask@entry=false)
at drivers/tty/sysrq.c:602
#5 0xc000000000b7506c in write_sysrq_trigger (file=<optimized out>, buf=<optimized out>,
count=2, ppos=<optimized out>) at drivers/tty/sysrq.c:1163
#6 0xc00000000069a7bc in pde_write (ppos=<optimized out>, count=<optimized out>,
buf=<optimized out>, file=<optimized out>, pde=0xc00000000362cb40) at fs/proc/inode.c:340
#7 proc_reg_write (file=<optimized out>, buf=<optimized out>, count=<optimized out>,
ppos=<optimized out>) at fs/proc/inode.c:352
#8 0xc0000000005b3bbc in vfs_write (file=file@entry=0xc000000006aa6b00,
buf=buf@entry=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>,
count=count@entry=2, pos=pos@entry=0xc00000000670bda0) at fs/read_write.c:582
#9 0xc0000000005b4264 in ksys_write (fd=<optimized out>,
buf=0x61f498b4f60 <error: Cannot access memory at address 0x61f498b4f60>, count=2)
at fs/read_write.c:637
#10 0xc00000000002ea2c in system_call_exception (regs=0xc00000000670be80, r0=<optimized out>)
at arch/powerpc/kernel/syscall.c:171
#11 0xc00000000000c270 in system_call_vectored_common ()
at arch/powerpc/kernel/interrupt_64.S:192
--------
Nick adds:
So this now saves regs as though it was an interrupt taken in the
caller, at the instruction after the call to ppc_save_regs, whereas
previously the NIP was there, but R1 came from the caller's caller and
that mismatch is what causes gdb's dwarf unwinder to go haywire.
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> Fixes: d16a58f8854b1 ("powerpc: Improve ppc_save_regs()") Reivewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230615091047.90433-1-adityag@linux.ibm.com
Naveen N Rao [Fri, 9 Jun 2023 03:45:01 +0000 (09:15 +0530)]
powerpc/ftrace: Disable ftrace on ppc32 if using clang
Ftrace on ppc32 expects a three instruction sequence at the beginning of
each function when specifying -pg:
mflr r0
stw r0,4(r1)
bl _mcount
This is the case with all supported versions of gcc. Clang however emits
a branch to _mcount after the function prologue, similar to the pre
-mprofile-kernel ABI on ppc64. This is not supported.
Disable ftrace on ppc32 if using clang for now. This can be re-enabled
later if clang picks up support for -fpatchable-function-entry on ppc32.
Colin Ian King [Thu, 8 Jun 2023 09:58:49 +0000 (10:58 +0100)]
powerpc/powernv/sriov: perform null check on iov before dereferencing iov
Currently pointer iov is being dereferenced before the null check of iov
which can lead to null pointer dereference errors. Fix this by moving the
iov null check before the dereferencing.
Detected using cppcheck static analysis:
linux/arch/powerpc/platforms/powernv/pci-sriov.c:597:12: warning: Either
the condition '!iov' is redundant or there is possible null pointer
dereference: iov. [nullPointerRedundantCheck]
num_vfs = iov->num_vfs;
^
Benjamin Gray [Mon, 19 Jun 2023 07:36:28 +0000 (17:36 +1000)]
selftests/powerpc/dexcr: Add DEXCR status utility lsdexcr
Add a utility 'lsdexcr' to print the current DEXCR status. Useful for
quickly checking the status such as when debugging test failures or
verifying the new default DEXCR does what you want (for userspace at
least). Example output:
Benjamin Gray [Mon, 19 Jun 2023 07:36:27 +0000 (17:36 +1000)]
selftests/powerpc: Add more utility macros
Adds _MSG assertion variants to provide more context behind why a
failure occurred. Also include unistd.h for _exit() and stdio.h for
fprintf(), and move ARRAY_SIZE macro to utils.h.
The _MSG variants and ARRAY_SIZE will be used by the following
DEXCR selftests.
Benjamin Gray [Mon, 19 Jun 2023 07:36:26 +0000 (17:36 +1000)]
powerpc/ptrace: Expose HASHKEYR register to ptrace
The HASHKEYR register contains a secret per-process key to enable unique
hashes per process. In general it should not be exposed to userspace
at all and a regular process has no need to know its key.
However, checkpoint restore in userspace (CRIU) functionality requires
that a process be able to set the HASHKEYR of another process, otherwise
existing hashes on the stack would be invalidated by a new random key.
Exposing HASHKEYR in this way also makes it appear in core dumps, which
is a security concern. Multiple threads may share a key, for example
just after a fork() call, where the kernel cannot know if the child is
going to return back along the parent's stack. If such a thread is
coerced into making a core dump, then the HASHKEYR value will be
readable and able to be used against all other threads sharing that key,
effectively undoing any protection offered by hashst/hashchk.
Therefore we expose HASHKEYR to ptrace when CONFIG_CHECKPOINT_RESTORE is
enabled, providing a choice of increased security or migratable ROP
protected processes. This is similar to how ARM exposes its PAC keys.
Benjamin Gray [Mon, 19 Jun 2023 07:36:26 +0000 (17:36 +1000)]
powerpc/ptrace: Expose DEXCR and HDEXCR registers to ptrace
The DEXCR register is of interest when ptracing processes. Currently it
is static, but eventually will be dynamically controllable by a process.
If a process can control its own, then it is useful for it to be
ptrace-able to (e.g., for checkpoint-restore functionality).
It is also relevant to core dumps (the NPHIE aspect in particular),
which use the ptrace mechanism (or is it the other way around?) to
decide what to dump. The HDEXCR is useful here too, as the NPHIE aspect
may be set in the HDEXCR without being set in the DEXCR. Although the
HDEXCR is per-cpu and we don't track it in the task struct (it's useless
in normal operation), it would be difficult to imagine why a hypervisor
would set it to different values within a guest. A hypervisor cannot
safely set NPHIE differently at least, as that would break programs.
Expose a read-only view of the userspace DEXCR and HDEXCR to ptrace.
The HDEXCR is always readonly, and is useful for diagnosing the core
dumps (as the HDEXCR may set NPHIE without the DEXCR setting it).
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Reviewed-by: Russell Currey <ruscur@russell.cc>
[mpe: Use lower_32_bits() rather than open coding] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230616034846.311705-7-bgray@linux.ibm.com
Benjamin Gray [Mon, 19 Jun 2023 07:36:26 +0000 (17:36 +1000)]
powerpc/dexcr: Support userspace ROP protection
The ISA 3.1B hashst and hashchk instructions use a per-cpu SPR HASHKEYR
to hold a key used in the hash calculation. This key should be different
for each process to make it harder for a malicious process to recreate
valid hash values for a victim process.
Add support for storing a per-thread hash key, and setting/clearing
HASHKEYR appropriately.
Benjamin Gray [Mon, 19 Jun 2023 07:36:25 +0000 (17:36 +1000)]
powerpc/dexcr: Handle hashchk exception
Recognise and pass the appropriate signal to the user program when a
hashchk instruction triggers. This is independent of allowing
configuration of DEXCR[NPHIE], as a hypervisor can enforce this aspect
regardless of the kernel.
The signal mirrors how ARM reports their similar check failure. For
example, their FPAC handler in arch/arm64/kernel/traps.c do_el0_fpac()
does this. When we fail to read the instruction that caused the fault
we send a segfault, similar to how emulate_math() does it.
Benjamin Gray [Mon, 19 Jun 2023 07:36:25 +0000 (17:36 +1000)]
powerpc/dexcr: Add initial Dynamic Execution Control Register (DEXCR) support
ISA 3.1B introduces the Dynamic Execution Control Register (DEXCR). It
is a per-cpu register that allows control over various CPU behaviours
including branch hint usage, indirect branch speculation, and
hashst/hashchk support.
Add some definitions and basic support for the DEXCR in the kernel.
Right now it just
* Initialises the DEXCR and HASHKEYR to a fixed value when a CPU
onlines.
* Clears them in reset_sprs().
* Detects when the NPHIE aspect is supported (the others don't get
looked at in this series, so there's no need to waste a CPU_FTR
on them).
We initialise the HASHKEYR to ensure that all cores have the same key,
so an HV enforced NPHIE + swapping cores doesn't randomly crash a
process using hash instructions. The stores to HASHKEYR are
unconditional because the ISA makes no mention of the SPR being missing
if support for doing the hashes isn't present. So all that would happen
is the HASHKEYR value gets ignored. This helps slightly if NPHIE
detection fails; e.g., we currently only detect it on pseries.
Benjamin Gray [Mon, 19 Jun 2023 07:36:25 +0000 (17:36 +1000)]
powerpc/ptrace: Add missing <linux/regset.h> include
ptrace-decl.h uses user_regset_get2_fn (among other things) from
regset.h. While all current users of ptrace-decl.h include regset.h
before it anyway, it adds an implicit ordering dependency and breaks
source tooling that tries to inspect ptrace-decl.h by itself.
Benjamin Gray [Mon, 19 Jun 2023 07:36:24 +0000 (17:36 +1000)]
powerpc/book3s: Add missing <linux/sched.h> include
The functions here use struct task_struct fields, so need to import
the full definition from <linux/sched.h>. The <asm/current.h> header
that defines current only forward declares struct task_struct.
Failing to include this <linux/sched.h> header leads to a compilation
error when a translation unit does not also include <linux/sched.h>
indirectly.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230616034846.311705-2-bgray@linux.ibm.com
Nicholas Piggin [Wed, 7 Jun 2023 10:10:24 +0000 (20:10 +1000)]
powerpc/64s: Fix VAS mm use after free
The refcount on mm is dropped before the coprocessor is detached.
Reported-by: Sachin Sant <sachinp@linux.ibm.com> Fixes: 7bc6f71bdff5f ("powerpc/vas: Define and use common vas_window struct") Fixes: b22f2d88e435c ("powerpc/pseries/vas: Integrate API with open/close windows") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230607101024.14559-1-npiggin@gmail.com
Nicholas Piggin [Tue, 6 Jun 2023 13:24:46 +0000 (23:24 +1000)]
powerpc: merge 32-bit and 64-bit _switch implementation
The _switch stack frame setup are substantially the same, so are the
comments. The difference in how the stack and current are switched,
and other hardware and software housekeeping is done is moved into
macros.
Nicholas Piggin [Tue, 6 Jun 2023 13:24:44 +0000 (23:24 +1000)]
powerpc/32: Remove sync from _switch
64-bit has removed the sync from _switch since commit 9145effd626d1
("powerpc/64: Drop explicit hwsync in context switch"). The same
logic there should apply to 32-bit. Remove the sync and replace with
a placeholder comment (32 and 64 will be merged with a later change).
Nicholas Piggin [Tue, 6 Jun 2023 13:24:43 +0000 (23:24 +1000)]
powerpc/64: Rearrange 64-bit _switch to prepare for 32/64 merge
More some 64-bit specifics out from the function epilogue and rearrange
this to be a bit neater, use 32-bit mem ops for CR save/restore, and
change some register numbers.
This is preparation to consolidate 32-bit and 64-bit switch code.
Nicholas Piggin [Tue, 6 Jun 2023 13:24:42 +0000 (23:24 +1000)]
powerpc/64s: move stack SLB pinning out of line from _switch
The large hunk of SLB pinning in _switch asm code makes it more
difficult to see everything else that's going on. It is a less important
path now, so icache and fetch footprint overhead can be avoided.
Move context switch stack SLB pinning out of line.
Nicholas Piggin [Tue, 6 Jun 2023 09:38:32 +0000 (19:38 +1000)]
powerpc/64s: Remove support for ELFv1 little endian userspace
ELFv2 was introduced together with little-endian. ELFv1 with LE has
never been a thing. The GNU toolchain can create such a beast, but
anyone doing that is a maniac who needs to be stopped so I consider
this patch a feature.
Nicholas Piggin [Tue, 6 Jun 2023 09:38:31 +0000 (19:38 +1000)]
powerpc/64: Use -mprofile-kernel for big endian ELFv2 kernels
-mprofile-kernel is an optimised calling convention for mcount that
Linux has only implemented with the ELFv2 ABI, so it was disabled for
big endian kernels. However it does work with ELFv2 big endian, so let's
allow that if the compiler supports it.
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230606093832.199712-4-npiggin@gmail.com
Nicholas Piggin [Tue, 6 Jun 2023 09:38:30 +0000 (19:38 +1000)]
powerpc/64: Make ELFv2 the default for big-endian builds
All supported toolchains now support ELFv2 on big-endian, so flip the
default on this and hide the option behind EXPERT for the purpose of
bug hunting.
Nicholas Piggin [Tue, 6 Jun 2023 09:38:29 +0000 (19:38 +1000)]
powerpc/64: Force ELFv2 when building with LLVM linker
The LLVM linker does not support ELFv1 at all, so BE kernels must be
built with ELFv2. The LLD version check was added to be conservative,
LLD simply fails to link ELFv1 entirely, effectively requiring LLD >= 15
and ELFv2 for BE builds. Instead remove that restriction until proven
otherwise (LLD 14.0 links a booting ELFv2 BE vmlinux for me).
The minimum GNU binutils has increased such that ELFv2 is always
supported, so remove that check while we're here.
Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230606093832.199712-2-npiggin@gmail.com
Nicholas Piggin [Tue, 6 Jun 2023 06:48:30 +0000 (16:48 +1000)]
powerpc/build: Remove -pipe from compilation flags
x86 removed -pipe in commit 437e88ab8f9e2 ("x86/build: Remove -pipe from
KBUILD_CFLAGS") and the newer arm64 and riscv seem to have never used it,
so that seems to be the way the world's going.
Compile performance building defconfig on a POWER10 PowerNV system
was in the noise after 10 builds each. No point in adding options unless
they help something, so remove it.
Nicholas Piggin [Tue, 6 Jun 2023 06:46:56 +0000 (16:46 +1000)]
powerpc/boot: Separate BOOTCFLAGS from BOOTASFLAGS
BOOTCFLAGS no longer contains anything that BOOTASFLAGS needs (except
-pipe). Separate them to avoid fragility with cross-contamination of
flags which has caused several build problems.
Uwe Kleine-König [Thu, 25 May 2023 20:56:22 +0000 (22:56 +0200)]
powerpc: Switch i2c drivers back to use .probe()
After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then 03c835f498b5 ("i2c: Switch .probe() to not take an id parameter")
convert back to (the new) .probe() to be able to eventually drop
.probe_new() from struct i2c_driver.
Uwe Kleine-König [Tue, 23 May 2023 19:50:53 +0000 (21:50 +0200)]
macintosh: Switch i2c drivers back to use .probe()
After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then 03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert
back to (the new) .probe() to be able to eventually drop .probe_new() from
struct i2c_driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Jean Delvare <jdelvare@suse.de> Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230523195053.464138-1-u.kleine-koenig@pengutronix.de
Christophe Leroy [Mon, 5 Jun 2023 08:58:35 +0000 (10:58 +0200)]
powerpc/signal32: Force inlining of __unsafe_save_user_regs() and save_tm_user_regs_unsafe()
Looking at generated code for handle_signal32() shows calls to a
function called __unsafe_save_user_regs.constprop.0 while user access
is open.
And that __unsafe_save_user_regs.constprop.0 function has two nops at
the begining, allowing it to be traced, which is unexpected during
user access open window.
The solution could be to mark __unsafe_save_user_regs() no trace, but
to be on the safe side the most efficient is to flag it __always_inline
as already done for function __unsafe_restore_general_regs(). The
function is relatively small and only called twice, so the size
increase will remain in the noise.
Do the same with save_tm_user_regs_unsafe() as it may suffer the
same issue.
Christophe Leroy [Mon, 5 Jun 2023 08:55:26 +0000 (10:55 +0200)]
powerpc/interrupt: Don't read MSR from interrupt_exit_kernel_prepare()
A disassembly of interrupt_exit_kernel_prepare() shows a useless read
of MSR register. This is shown by r9 being re-used immediately without
doing anything with the value read.
Activating KCSAN on a 32 bits architecture leads to the following
link-time failure:
LD .tmp_vmlinux.kallsyms1
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_load':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_load_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_store':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_store_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_exchange':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_exchange_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_fetch_add':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_fetch_add_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_fetch_sub':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_fetch_sub_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_fetch_and':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_fetch_and_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_fetch_or':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_fetch_or_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_fetch_xor':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_fetch_xor_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_fetch_nand':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_fetch_nand_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_compare_exchange_strong':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_compare_exchange_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_compare_exchange_weak':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_compare_exchange_8'
powerpc64-linux-ld: kernel/kcsan/core.o: in function `__tsan_atomic64_compare_exchange_val':
kernel/kcsan/core.c:1273: undefined reference to `__atomic_compare_exchange_8'
32 bits architectures don't have 64 bits atomic builtins. Only
include DEFINE_TSAN_ATOMIC_OPS(64) on 64 bits architectures.
Fixes: 0f8ad5f2e934 ("kcsan: Add support for atomic builtins") Suggested-by: Marco Elver <elver@google.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Marco Elver <elver@google.com> Acked-by: Marco Elver <elver@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/d9c6afc28d0855240171a4e0ad9ffcdb9d07fceb.1683892665.git.christophe.leroy@csgroup.eu
Nicholas Piggin [Thu, 8 Jun 2023 02:45:04 +0000 (12:45 +1000)]
KVM: PPC: Update MAINTAINERS
Michael is merging KVM PPC patches via the powerpc tree and KVM topic
branches. He doesn't necessarily have time to be across all of KVM so
is reluctant to call himself maintainer, but for the mechanics of how
patches flow upstream, it is maintained and does make sense to have
some contact people in MAINTAINERS.
So add Michael Ellerman as KVM PPC maintainer and myself as reviewer.
Split out the subarchs that don't get so much attention.
Michael Ellerman [Wed, 31 May 2023 12:50:23 +0000 (22:50 +1000)]
MAINTAINERS: Exclude m68k-only drivers from powerpc entry
The powerpc section has a "F:" entry for drivers/macintosh, matching all
files in or below drivers/macintosh. That is correct for the most part,
but there are a couple of m68k-only drivers in the directory, so exclude
those.
Maninder Singh [Mon, 29 May 2023 11:13:37 +0000 (16:43 +0530)]
powerpc/xmon: Use KSYM_NAME_LEN in array size
kallsyms_lookup() which in turn calls kallsyms_lookup_buildid() writes
to index "KSYM_NAME_LEN - 1".
Thus the array passed as namebuf to kallsyms_lookup() should be
KSYM_NAME_LEN in size.
In xmon.c the array was defined to be "128" bytes directly, without
using KSYM_NAME_LEN. Commit b8a94bfb3395 ("kallsyms: increase maximum
kernel symbol length to 512") changed the value to 512, but missed
updating the xmon code.
Fixes: b8a94bfb3395 ("kallsyms: increase maximum kernel symbol length to 512") Cc: stable@vger.kernel.org # v6.1+ Co-developed-by: Onkarnath <onkarnath.1@samsung.com> Signed-off-by: Onkarnath <onkarnath.1@samsung.com> Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
[mpe: Tweak change log wording and fix commit reference] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230529111337.352990-2-maninder1.s@samsung.com
Gaurav Batra [Thu, 25 May 2023 14:34:54 +0000 (09:34 -0500)]
powerpc/iommu: Limit number of TCEs to 512 for H_STUFF_TCE hcall
Currently in tce_freemulti_pSeriesLP() there is no limit on how many
TCEs are passed to the H_STUFF_TCE hcall. This has not caused an issue
until now, but newer firmware releases have started enforcing a limit of
512 TCEs per call.
The limit is correct per the specification (PAPR v2.12 § 14.5.4.2.3).
The code has been in it's current form since it was initially merged.
Cc: stable@vger.kernel.org Signed-off-by: Gaurav Batra <gbatra@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
[mpe: Tweak change log wording & add PAPR reference] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230525143454.56878-1-gbatra@linux.vnet.ibm.com
Michael Ellerman [Thu, 25 May 2023 02:43:21 +0000 (12:43 +1000)]
powerpc/crypto: Fix aes-gcm-p10 link errors
The recently added P10 AES/GCM code added some files containing
CRYPTOGAMS perl-asm code which are near duplicates of the p8 files
found in drivers/crypto/vmx.
In particular the newly added files produce functions with identical
names to the existing code.
When the kernel is built with CONFIG_CRYPTO_AES_GCM_P10=y and
CONFIG_CRYPTO_DEV_VMX_ENCRYPT=y that leads to link errors, eg:
ld: drivers/crypto/vmx/aesp8-ppc.o: in function `aes_p8_set_encrypt_key':
(.text+0xa0): multiple definition of `aes_p8_set_encrypt_key'; arch/powerpc/crypto/aesp8-ppc.o:(.text+0xa0): first defined here
...
ld: drivers/crypto/vmx/ghashp8-ppc.o: in function `gcm_ghash_p8':
(.text+0x140): multiple definition of `gcm_ghash_p8'; arch/powerpc/crypto/ghashp8-ppc.o:(.text+0x2e4): first defined here
Fix it for now by renaming the newly added files and functions to use
"p10" instead of "p8" in the names.
Fixes: 45a4672b9a6e ("crypto: p10-aes-gcm - Update Kconfig and Makefile") Tested-by: Vishal Chourasia <vishalc@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230525150501.37081-1-mpe@ellerman.id.au
Michael Ellerman [Fri, 19 May 2023 11:38:06 +0000 (21:38 +1000)]
powerpc/mm: Reinstate ARCH_FORCE_MAX_ORDER ranges
Commit 1e8fed873e74 ("powerpc: drop ranges for definition of
ARCH_FORCE_MAX_ORDER") removed the limits on the possible values for
ARCH_FORCE_MAX_ORDER.
However removing the ranges entirely causes some common work flows to
break. For example building a defconfig (which uses 64K pages), changing
the page size to 4K, and rebuilding used to work, because
ARCH_FORCE_MAX_ORDER would be clamped to 12 by the ranges.
With the ranges removed it creates a kernel that builds but crashes at
boot:
kernel BUG at mm/huge_memory.c:470!
Oops: Exception in kernel mode, sig: 5 [#1]
...
NIP hugepage_init+0x9c/0x278
LR do_one_initcall+0x80/0x320
Call Trace:
do_one_initcall+0x80/0x320
kernel_init_freeable+0x304/0x3ac
kernel_init+0x30/0x1a0
ret_from_kernel_user_thread+0x14/0x1c
The reasoning for removing the ranges was that some of the values were
too large. So take that into account and limit the maximums to 10 which
is the default max, except for the 4K case which uses 12.
Gaurav Batra [Fri, 5 May 2023 18:47:01 +0000 (13:47 -0500)]
powerpc/iommu: Incorrect DDW Table is referenced for SR-IOV device
For an SR-IOV device, while enabling DDW, a new table is created and
added at index 1 in the group. In the below 2 scenarios, the table is
incorrectly referenced at index 0 (which is where the table is for
default DMA window).
1. When adding DDW
This issue is exposed with "slub_debug". Error thrown out from
dma_iommu_dma_supported()
Warning: IOMMU offset too big for device mask
mask: 0xffffffff, table offset: 0x800000000000000
2. During Dynamic removal of the PCI device.
Error is from iommu_tce_table_put() since a NULL table pointer is
passed in.
Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping") Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Gaurav Batra <gbatra@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230505184701.91613-1-gbatra@linux.vnet.ibm.com
Gaurav Batra [Thu, 4 May 2023 17:59:13 +0000 (12:59 -0500)]
powerpc/iommu: DMA address offset is incorrectly calculated with 2MB TCEs
When DMA window is backed by 2MB TCEs, the DMA address for the mapped
page should be the offset of the page relative to the 2MB TCE. The code
was incorrectly setting the DMA address to the beginning of the TCE
range.
Mellanox driver is reporting timeout trying to ENABLE_HCA for an SR-IOV
ethernet port, when DMA window is backed by 2MB TCEs.
Fixes: 387273118714 ("powerps/pseries/dma: Add support for 2M IOMMU page size") Cc: stable@vger.kernel.org # v5.16+ Signed-off-by: Gaurav Batra <gbatra@linux.vnet.ibm.com> Reviewed-by: Greg Joyce <gjoyce@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230504175913.83844-1-gbatra@linux.vnet.ibm.com
Jason Gunthorpe [Tue, 16 May 2023 00:12:31 +0000 (21:12 -0300)]
powerpc/iommu: Remove iommu_del_device()
Now that power calls iommu_device_register() and populates its groups
using iommu_ops->device_group it should not be calling
iommu_group_remove_device().
The core code owns the groups and all the other related iommu data, it
will clean it up automatically.
Remove the bus notifiers and explicit calls to
iommu_group_remove_device().
While mpc5200b.dtsi contains a device that this driver can bind to, the
only purpose of a bound device is to be used by the four exported functions
mpc52xx_lpbfifo_submit(), mpc52xx_lpbfifo_abort(), mpc52xx_lpbfifo_poll()
and mpc52xx_lpbfifo_start_xfer(). However there are no callers to this
function and so the driver is effectively superfluous and can be deleted.
Also drop some defines and a struct from <asm/mpc52xx.h> that are unused
now together with the declarations of the four mentioned functions.
Tom Rix [Fri, 28 Apr 2023 22:12:40 +0000 (18:12 -0400)]
powerpc/spufs: remove unneeded if-checks
For ppc64, gcc with W=1 reports
arch/powerpc/platforms/cell/spu_base.c:330:17: error:
suggest braces around empty body in an 'if' statement [-Werror=empty-body]
330 | ;
| ^
arch/powerpc/platforms/cell/spu_base.c:333:17: error:
suggest braces around empty body in an 'if' statement [-Werror=empty-body]
333 | ;
| ^
These if-checks do not do anything so remove them.
Signed-off-by: Tom Rix <trix@redhat.com> Fixes: 67207b9664a8 ("[PATCH] spufs: The SPU file system, base") Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230428221240.2679194-1-trix@redhat.com
Randy Dunlap [Sat, 29 Apr 2023 04:35:03 +0000 (21:35 -0700)]
powerpc: delete empty config entry for PPC_86xx
Drop an unused and empty "config" entry for PPC_86xx.
It has no keyword entries under it and the following line's
"menuconfig" for the same Kconfig symbol is what kconfig uses.
Michael Ellerman [Mon, 15 May 2023 12:40:08 +0000 (22:40 +1000)]
powerpc/crypto: Fix aes-gcm-p10 build when VSX=n
When VSX is disabled, eg. microwatt_defconfig, the build fails with:
In function ‘enable_kernel_vsx’,
inlined from ‘vsx_begin’ at arch/powerpc/crypto/aes-gcm-p10-glue.c:68:2,
inlined from ‘p10_aes_gcm_crypt.constprop’ at arch/powerpc/crypto/aes-gcm-p10-glue.c:244:2:
...
arch/powerpc/include/asm/switch_to.h:86:9: note: in expansion of macro ‘BUILD_BUG’
86 | BUILD_BUG();
| ^~~~~~~~~
Fix it by making the p10-aes-gcm code depend on VSX.
Hari Bathini [Tue, 25 Apr 2023 06:58:29 +0000 (12:28 +0530)]
powerpc/bpf: populate extable entries only during the last pass
Since commit 85e031154c7c ("powerpc/bpf: Perform complete extra passes
to update addresses"), two additional passes are performed to avoid
space and CPU time wastage on powerpc. But these extra passes led to
WARN_ON_ONCE() hits in bpf_add_extable_entry() as extable entries are
populated again, during the extra pass, without resetting the index.
Fix it by resetting entry index before repopulating extable entries,
if and when there is an additional pass.
Fixes: 85e031154c7c ("powerpc/bpf: Perform complete extra passes to update addresses") Cc: stable@vger.kernel.org # v6.3+ Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230425065829.18189-1-hbathini@linux.ibm.com
Linus Torvalds [Sun, 14 May 2023 19:32:34 +0000 (12:32 -0700)]
Merge tag 'cxl-fixes-6.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl
Pull compute express link fixes from Dan Williams:
- Fix a compilation issue with DEFINE_STATIC_SRCU() in the unit tests
- Fix leaking kernel memory to a root-only sysfs attribute
* tag 'cxl-fixes-6.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl: Add missing return to cdat read error path
tools/testing/cxl: Use DEFINE_STATIC_SRCU()
Linus Torvalds [Sun, 14 May 2023 16:54:38 +0000 (09:54 -0700)]
Merge tag 'parisc-for-6.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
- Fix encoding of swp_entry due to added SWP_EXCLUSIVE flag
- Include reboot.h to avoid gcc-12 compiler warning
* tag 'parisc-for-6.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix encoding of swp_entry due to added SWP_EXCLUSIVE flag
parisc: kexec: include reboot.h
Linus Torvalds [Sun, 14 May 2023 15:00:46 +0000 (08:00 -0700)]
Merge tag 'locking_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Borislav Petkov:
- Make sure __down_read_common() is always inlined so that the callers'
names land in traceevents output and thus the blocked function can be
identified
* tag 'locking_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rwsem: Add __always_inline annotation to __down_read_common() and inlined callers
Linus Torvalds [Sun, 14 May 2023 14:56:51 +0000 (07:56 -0700)]
Merge tag 'perf_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Make sure the PEBS buffer is flushed before reprogramming the
hardware so that the correct record sizes are used
- Update the sample size for AMD BRS events
- Fix a confusion with using the same on-stack struct with different
events in the event processing path
* tag 'perf_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/ds: Flush PEBS DS when changing PEBS_DATA_CFG
perf/x86: Fix missing sample size update on AMD BRS
perf/core: Fix perf_sample_data not properly initialized for different swevents in perf_tp_event()
Linus Torvalds [Sun, 14 May 2023 14:44:48 +0000 (07:44 -0700)]
Merge tag 'x86_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Borislav Petkov:
- Add the required PCI IDs so that the generic SMN accesses provided by
amd_nb.c work for drivers which switch to them. Add a PCI device ID
to k10temp's table so that latter is loaded on such systems too
* tag 'x86_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hwmon: (k10temp) Add PCI ID for family 19, model 78h
x86/amd_nb: Add PCI ID for family 19h model 78h
Linus Torvalds [Sun, 14 May 2023 14:39:15 +0000 (07:39 -0700)]
Merge tag 'timers_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Borislav Petkov:
- Prevent CPU state corruption when an active clockevent broadcast
device is replaced while the system is already in oneshot mode
* tag 'timers_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/broadcast: Make broadcast device replacement work correctly
Linus Torvalds [Sun, 14 May 2023 00:45:39 +0000 (17:45 -0700)]
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Some ext4 bug fixes (mostly to address Syzbot reports)"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: bail out of ext4_xattr_ibody_get() fails for any reason
ext4: add bounds checking in get_max_inline_xattr_value_size()
ext4: add indication of ro vs r/w mounts in the mount message
ext4: fix deadlock when converting an inline directory in nojournal mode
ext4: improve error recovery code paths in __ext4_remount()
ext4: improve error handling from ext4_dirhash()
ext4: don't clear SB_RDONLY when remounting r/w until quota is re-enabled
ext4: check iomap type only if ext4_iomap_begin() does not fail
ext4: avoid a potential slab-out-of-bounds in ext4_group_desc_csum
ext4: fix data races when using cached status extents
ext4: avoid deadlock in fs reclaim with page writeback
ext4: fix invalid free tracking in ext4_xattr_move_to_block()
ext4: remove a BUG_ON in ext4_mb_release_group_pa()
ext4: allow ext4_get_group_info() to fail
ext4: fix lockdep warning when enabling MMP
ext4: fix WARNING in mb_find_extent
Linus Torvalds [Sun, 14 May 2023 00:37:32 +0000 (17:37 -0700)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fix from James Bottomley:
"A single small fix for the UFS driver to fix a power management
failure"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: core: Fix I/O hang that occurs when BKOPS fails in W-LUN suspend
Helge Deller [Sat, 13 May 2023 20:30:06 +0000 (22:30 +0200)]
parisc: Fix encoding of swp_entry due to added SWP_EXCLUSIVE flag
Fix the __swp_offset() and __swp_entry() macros due to commit 6d239fc78c0b
("parisc/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE") which introduced the
SWP_EXCLUSIVE flag by reusing the _PAGE_ACCESSED flag.
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de> Tested-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Helge Deller <deller@gmx.de> Fixes: 6d239fc78c0b ("parisc/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE") Cc: <stable@vger.kernel.org> # v6.3+
Theodore Ts'o [Fri, 12 May 2023 19:16:27 +0000 (15:16 -0400)]
ext4: bail out of ext4_xattr_ibody_get() fails for any reason
In ext4_update_inline_data(), if ext4_xattr_ibody_get() fails for any
reason, it's best if we just fail as opposed to stumbling on,
especially if the failure is EFSCORRUPTED.
Theodore Ts'o [Fri, 12 May 2023 19:11:02 +0000 (15:11 -0400)]
ext4: add bounds checking in get_max_inline_xattr_value_size()
Normally the extended attributes in the inode body would have been
checked when the inode is first opened, but if someone is writing to
the block device while the file system is mounted, it's possible for
the inode table to get corrupted. Add bounds checking to avoid
reading beyond the end of allocated memory if this happens.
Theodore Ts'o [Fri, 12 May 2023 18:49:57 +0000 (14:49 -0400)]
ext4: add indication of ro vs r/w mounts in the mount message
Whether the file system is mounted read-only or read/write is more
important than the quota mode, which we are already printing. Add the
ro vs r/w indication since this can be helpful in debugging problems
from the console log.
Theodore Ts'o [Sun, 7 May 2023 01:04:01 +0000 (21:04 -0400)]
ext4: fix deadlock when converting an inline directory in nojournal mode
In no journal mode, ext4_finish_convert_inline_dir() can self-deadlock
by calling ext4_handle_dirty_dirblock() when it already has taken the
directory lock. There is a similar self-deadlock in
ext4_incvert_inline_data_nolock() for data files which we'll fix at
the same time.
Theodore Ts'o [Sat, 6 May 2023 02:20:29 +0000 (22:20 -0400)]
ext4: improve error recovery code paths in __ext4_remount()
If there are failures while changing the mount options in
__ext4_remount(), we need to restore the old mount options.
This commit fixes two problem. The first is there is a chance that we
will free the old quota file names before a potential failure leading
to a use-after-free. The second problem addressed in this commit is
if there is a failed read/write to read-only transition, if the quota
has already been suspended, we need to renable quota handling.
Theodore Ts'o [Sat, 6 May 2023 15:59:13 +0000 (11:59 -0400)]
ext4: improve error handling from ext4_dirhash()
The ext4_dirhash() will *almost* never fail, especially when the hash
tree feature was first introduced. However, with the addition of
support of encrypted, casefolded file names, that function can most
certainly fail today.
So make sure the callers of ext4_dirhash() properly check for
failures, and reflect the errors back up to their callers.
Theodore Ts'o [Sat, 6 May 2023 01:02:30 +0000 (21:02 -0400)]
ext4: don't clear SB_RDONLY when remounting r/w until quota is re-enabled
When a file system currently mounted read/only is remounted
read/write, if we clear the SB_RDONLY flag too early, before the quota
is initialized, and there is another process/thread constantly
attempting to create a directory, it's possible to trigger the
WARN_ON_ONCE(dquot_initialize_needed(inode));
in ext4_xattr_block_set(), with the following stack trace:
Baokun Li [Fri, 5 May 2023 13:24:29 +0000 (21:24 +0800)]
ext4: check iomap type only if ext4_iomap_begin() does not fail
When ext4_iomap_overwrite_begin() calls ext4_iomap_begin() map blocks may
fail for some reason (e.g. memory allocation failure, bare disk write), and
later because "iomap->type ! = IOMAP_MAPPED" triggers WARN_ON(). When ext4
iomap_begin() returns an error, it is normal that the type of iomap->type
may not match the expectation. Therefore, we only determine if iomap->type
is as expected when ext4_iomap_begin() is executed successfully.
Replace
le16_to_cpu(sbi->s_es->s_desc_size)
with
sbi->s_desc_size
It reduces ext4's compiled text size, and makes the code more efficient
(we remove an extra indirect reference and a potential byte
swap on big endian systems), and there is no downside. It also avoids the
potential KASAN / syzkaller failure, as a bonus.
Jan Kara [Thu, 4 May 2023 12:55:24 +0000 (14:55 +0200)]
ext4: fix data races when using cached status extents
When using cached extent stored in extent status tree in tree->cache_es
another process holding ei->i_es_lock for reading can be racing with us
setting new value of tree->cache_es. If the compiler would decide to
refetch tree->cache_es at an unfortunate moment, it could result in a
bogus in_range() check. Fix the possible race by using READ_ONCE() when
using tree->cache_es only under ei->i_es_lock for reading.
Jan Kara [Thu, 4 May 2023 12:47:23 +0000 (14:47 +0200)]
ext4: avoid deadlock in fs reclaim with page writeback
Ext4 has a filesystem wide lock protecting ext4_writepages() calls to
avoid races with switching of journalled data flag or inode format. This
lock can however cause a deadlock like:
CPU0 CPU1
ext4_writepages()
percpu_down_read(sbi->s_writepages_rwsem);
ext4_change_inode_journal_flag()
percpu_down_write(sbi->s_writepages_rwsem);
- blocks, all readers block from now on
ext4_do_writepages()
ext4_init_io_end()
kmem_cache_zalloc(io_end_cachep, GFP_KERNEL)
fs_reclaim frees dentry...
dentry_unlink_inode()
iput() - last ref =>
iput_final() - inode dirty =>
write_inode_now()...
ext4_writepages() tries to acquire sbi->s_writepages_rwsem
and blocks forever
Make sure we cannot recurse into filesystem reclaim from writeback code
to avoid the deadlock.
ext4: fix invalid free tracking in ext4_xattr_move_to_block()
In ext4_xattr_move_to_block(), the value of the extended attribute
which we need to move to an external block may be allocated by
kvmalloc() if the value is stored in an external inode. So at the end
of the function the code tried to check if this was the case by
testing entry->e_value_inum.
However, at this point, the pointer to the xattr entry is no longer
valid, because it was removed from the original location where it had
been stored. So we could end up calling kvfree() on a pointer which
was not allocated by kvmalloc(); or we could also potentially leak
memory by not freeing the buffer when it should be freed. Fix this by
storing whether it should be freed in a separate variable.
projects / users / jedix / linux-maple.git / log