Ravi Bangoria [Thu, 23 Jul 2020 09:08:13 +0000 (14:38 +0530)]
powerpc/watchpoint: Remove 512 byte boundary
Power10 has removed 512 bytes boundary from match criteria i.e. the watch
range can cross 512 bytes boundary.
Note: ISA 3.1 Book III 9.4 match criteria includes 512 byte limit but that
is a documentation mistake and hopefully will be fixed in the next version
of ISA. Though, ISA 3.1 change log mentions about removal of 512B boundary:
Multiple DEAW:
Added a second Data Address Watchpoint. [H]DAR is
set to the first byte of overlap. 512B boundary is
removed.
Ravi Bangoria [Thu, 23 Jul 2020 09:08:12 +0000 (14:38 +0530)]
powerpc/watchpoint: Return available watchpoints dynamically
So far Book3S Powerpc supported only one watchpoint. Power10 is
introducing 2nd DAWR. Enable 2nd DAWR support for Power10.
Availability of 2nd DAWR will depend on CPU_FTR_DAWR1.
Ravi Bangoria [Thu, 23 Jul 2020 09:08:11 +0000 (14:38 +0530)]
powerpc/watchpoint: Guest support for 2nd DAWR hcall
2nd DAWR can be set/unset using H_SET_MODE hcall with resource value 5.
Enable powervm guest support with that. This has no effect on kvm guest
because kvm will return error if guest does hcall with resource value 5.
Ravi Bangoria [Thu, 23 Jul 2020 09:08:09 +0000 (14:38 +0530)]
powerpc/watchpoint: Set CPU_FTR_DAWR1 based on pa-features bit
As per the PAPR, bit 0 of byte 64 in pa-features property indicates
availability of 2nd DAWR registers. i.e. If this bit is set, 2nd
DAWR is present, otherwise not. Host generally uses "cpu-features",
which masks "pa-features". But "cpu-features" are still not used for
guests and thus this change is mostly applicable for guests only.
Ravi Bangoria [Thu, 23 Jul 2020 09:08:07 +0000 (14:38 +0530)]
powerpc/watchpoint: Enable watchpoint functionality on power10 guest
CPU_FTR_DAWR is by default enabled for host via CPU_FTRS_DT_CPU_BASE
(controlled by CONFIG_PPC_DT_CPU_FTRS). But cpu-features device-tree
node is not PAPR compatible and thus not yet used by kvm or pHyp
guests. Enable watchpoint functionality on power10 guest (both kvm
and powervm) by adding CPU_FTR_DAWR to CPU_FTRS_POWER10. Note that
this change does not enable 2nd DAWR support.
Ravi Bangoria [Thu, 23 Jul 2020 09:08:06 +0000 (14:38 +0530)]
powerpc/watchpoint: Fix DAWR exception for CACHEOP
'ea' returned by analyse_instr() needs to be aligned down to cache
block size for CACHEOP instructions. analyse_instr() does not set
size for CACHEOP, thus size also needs to be calculated manually.
Fixes: 27985b2a640e ("powerpc/watchpoint: Don't ignore extraneous exceptions blindly") Fixes: 74c6881019b7 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint") Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200723090813.303838-4-ravi.bangoria@linux.ibm.com
Ravi Bangoria [Thu, 23 Jul 2020 09:08:05 +0000 (14:38 +0530)]
powerpc/watchpoint: Fix DAWR exception constraint
Pedro Miraglia Franco de Carvalho noticed that on p8/p9, DAR value is
inconsistent with different type of load/store. Like for byte,word
etc. load/stores, DAR is set to the address of the first byte of
overlap between watch range and real access. But for quadword load/
store it's sometime set to the address of the first byte of real
access whereas sometime set to the address of the first byte of
overlap. This issue has been fixed in p10. In p10(ISA 3.1), DAR is
always set to the address of the first byte of overlap. Commit 27985b2a640e
("powerpc/watchpoint: Don't ignore extraneous exceptions blindly")
wrongly assumes that DAR is set to the address of the first byte of
overlap for all load/stores on p8/p9 as well. Fix that. With the fix,
we now rely on 'ea' provided by analyse_instr(). If analyse_instr()
fails, generate event unconditionally on p8/p9, and on p10 generate
event only if DAR is within a DAWR range.
Note: 8xx is not affected.
Fixes: 27985b2a640e ("powerpc/watchpoint: Don't ignore extraneous exceptions blindly") Fixes: 74c6881019b7 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint") Reported-by: Pedro Miraglia Franco de Carvalho <pedromfc@br.ibm.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200723090813.303838-3-ravi.bangoria@linux.ibm.com
Ravi Bangoria [Thu, 23 Jul 2020 09:08:04 +0000 (14:38 +0530)]
powerpc/watchpoint: Fix 512 byte boundary limit
Milton Miller reported that we are aligning start and end address to
wrong size SZ_512M. It should be SZ_512. Fix that.
While doing this change I also found a case where ALIGN() comparison
fails. Within a given aligned range, ALIGN() of two addresses does not
match when start address is pointing to the first byte and end address
is pointing to any other byte except the first one. But that's not true
for ALIGN_DOWN(). ALIGN_DOWN() of any two addresses within that range
will always point to the first byte. So use ALIGN_DOWN() instead of
ALIGN().
Fixes: e68ef121c1f4 ("powerpc/watchpoint: Use builtin ALIGN*() macros") Reported-by: Milton Miller <miltonm@us.ibm.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Tested-by: Jordan Niethe <jniethe5@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200723090813.303838-2-ravi.bangoria@linux.ibm.com
powerpc/book3s64/pkey: Disable pkey on POWER6 and before
POWER6 only supports AMR update via privileged mode (MSR[PR] = 0,
SPRN_AMR=29) The PR=1 (userspace) alias for that SPR (SPRN_AMR=13) was
only supported from POWER7. Since we don't allow userspace modifying
of AMR value we should disable pkey support on P6 and before.
The hypervisor will still report pkey support via
"ibm,processor-storage-keys". Hence also check for P7 CPU_FTR bit to
decide on pkey support.
Fixes: f491fe3fb41e ("powerpc/book3s64/pkeys: Simplify the key initialization") Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200726132517.399076-1-aneesh.kumar@linux.ibm.com
Michael Ellerman [Fri, 24 Jul 2020 10:42:54 +0000 (20:42 +1000)]
powerpc/sstep: Fix incorrect CONFIG symbol in scv handling
When I "fixed" the ppc64e build in Nick's recent patch, I typoed the
CONFIG symbol, resulting in one that doesn't exist. Fix it to use the
correct symbol.
Michael Ellerman [Thu, 23 Jul 2020 23:02:26 +0000 (09:02 +1000)]
powerpc/test_emulate_sstep: Fix build error
ppc64_book3e_allmodconfig fails with:
arch/powerpc/lib/test_emulate_step.c: In function 'test_pld':
arch/powerpc/lib/test_emulate_step.c:113:7: error: implicit declaration of function 'cpu_has_feature'
113 | if (!cpu_has_feature(CPU_FTR_ARCH_31)) {
| ^~~~~~~~~~~~~~~
Michael Ellerman [Thu, 23 Jul 2020 07:43:44 +0000 (17:43 +1000)]
Merge branch 'scv' support into next
From Nick's cover letter:
Linux powerpc new system call instruction and ABI
System Call Vectored (scv) ABI
==============================
The scv instruction is introduced with POWER9 / ISA3, it comes with an
rfscv counter-part. The benefit of these instructions is
performance (trading slower SRR0/1 with faster LR/CTR registers, and
entering the kernel with MSR[EE] and MSR[RI] left enabled, which can
reduce MSR updates. The scv instruction has 128 levels (not enough to
cover the Linux system call space).
Assignment and advertisement
----------------------------
The proposal is to assign scv levels conservatively, and advertise
them with HWCAP feature bits as we add support for more.
Linux has not enabled FSCR[SCV] yet, so executing the scv instruction
will cause the kernel to log a "SCV facility unavilable" message, and
deliver a SIGILL with ILL_ILLOPC to the process. Linux has defined a
HWCAP2 bit PPC_FEATURE2_SCV for SCV support, but does not set it.
This change allocates the zero level ('scv 0'), advertised with
PPC_FEATURE2_SCV, which will be used to provide normal Linux system
calls (equivalent to 'sc').
Attempting to execute scv with other levels will cause a SIGILL to be
delivered the same as before, but will not log a "SCV facility
unavailable" message (because the processor facility is enabled).
Calling convention
------------------
The proposal is for scv 0 to provide the standard Linux system call
ABI with the following differences from sc convention[1]:
- LR is to be volatile across scv calls. This is necessary because the
scv instruction clobbers LR. From previous discussion, this should
be possible to deal with in GCC clobbers and CFI.
- cr1 and cr5-cr7 are volatile. This matches the C ABI and would allow
the kernel system call exit to avoid restoring the volatile cr
registers (although we probably still would anyway to avoid
information leaks).
- Error handling: The consensus among kernel, glibc, and musl is to
move to using negative return values in r3 rather than CR0[SO]=1 to
indicate error, which matches most other architectures, and is
closer to a function call.
Notes
-----
- r0,r4-r8 are documented as volatile in the ABI, but the kernel patch
as submitted currently preserves them. This is to leave room for
deciding which way to go with these. Some small benefit was found by
preserving them[1] but I'm not convinced it's worth deviating from
the C function call ABI just for this. Release code should follow
the ABI.
Michael Ellerman [Wed, 22 Jul 2020 05:53:15 +0000 (15:53 +1000)]
selftests/powerpc: Add test of memcmp at end of page
Update our memcmp selftest, to test the case where we're comparing up
to the end of a page and the subsequent page is not mapped. We have to
make sure we don't read off the end of the page and cause a fault.
We had a bug there in the past, fixed in commit d9470757398a ("powerpc/64: Fix memcmp reading past the end of src/dest").
powerpc/powernv/idle: Exclude mfspr on HID1, 4, 5 on P9 and above
POWER9 onwards the support for the registers HID1, HID4, HID5 has been
receded.
Although mfspr on the above registers worked in Power9, In Power10
simulator is unrecognized. Moving their assignment under the
check for machines lower than Power9
Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com> Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200721153708.89057-4-psampat@linux.ibm.com
Replace the variable name from using "pnv_first_spr_loss_level" to
"deep_spr_loss_state".
pnv_first_spr_loss_level is supposed to be the earliest state that
has OPAL_PM_LOSE_FULL_CONTEXT set, in other places the kernel uses the
"deep" states as terminology. Hence renaming the variable to be coherent
to its semantics.
powerpc/powernv/idle: Replace CPU feature check with PVR check
The POWER9 idle driver contains implementation-specific details that
means it is not suitable to run on any processor that implements ISA
v3.0 (e.g., POWER10), so only init the driver when running on a
POWER9.
powerpc/mm/hash64: Remove comment that is no longer valid
hash_low_64.S was removed in commit a43c0eb8364c ("powerpc/mm: Convert
4k insert from asm to C") and flush_hash_page() is no longer called
from any assembly routine.
Leonardo Bras [Tue, 7 Jul 2020 00:48:12 +0000 (21:48 -0300)]
KVM: PPC: Fix typo on H_DISABLE_AND_GET hcall
On PAPR+ the hcall() on 0x1B0 is called H_DISABLE_AND_GET, but got
defined as H_DISABLE_AND_GETC instead.
This define was introduced with a typo in commit <b13a96cfb055>
("[PATCH] powerpc: Extends HCALL interface for InfiniBand usage"), and was
later used without having the typo noticed.
Several device drivers hit EEH(Extended Error handling) when
triggering kdump on Pseries PowerVM. This patch implemented a reset of
the PHBs in pci general code when triggering kdump. PHB reset stop all
PCI transactions from normal kernel. We have tested the patch in
several enviroments:
- direct slot adapters
- adapters under the switch
- a VF adapter in PowerVM
- a VF adapter/adapter in KVM guest.
powerpc/64: Fix an out of date comment about MMIO ordering
This primitive has been renamed, but because it was spelled incorrectly in the
first place it must have escaped the fixup patch. As far as I can tell this
logic is still correct: smp_mb__after_spinlock() uses the default smp_mb()
implementation, which is "sync" rather than "hwsync" but those are the same
(though I'm not that familiar with PowerPC).
Currently prefixed instructions are dumped as two separate word
instructions. Use mread_instr() so that prefixed instructions are read
as such and update the incrementor in the loop to take this into
account.
'dump_func' is print_insn_powerpc() which comes from ppc-dis.c which is
taken from binutils. When this is updated prefixed instructions will be
disassembled.
Jordan Niethe [Tue, 2 Jun 2020 05:27:25 +0000 (15:27 +1000)]
powerpc: Add a ppc_inst_as_str() helper
There are quite a few places where instructions are printed, this is
done using a '%x' format specifier. With the introduction of prefixed
instructions, this does not work well. Currently in these places,
ppc_inst_val() is used for the value for %x so only the first word of
prefixed instructions are printed.
When the instructions are word instructions, only a single word should
be printed. For prefixed instructions both the prefix and suffix should
be printed. To accommodate both of these situations, instead of a '%x'
specifier use '%s' and introduce a helper, __ppc_inst_as_str() which
returns a char *. The char * __ppc_inst_as_str() returns is buffer that
is passed to it by the caller.
It is cumbersome to require every caller of __ppc_inst_as_str() to now
declare a buffer. To make it more convenient to use __ppc_inst_as_str(),
wrap it in a macro that uses a compound statement to allocate a buffer
on the caller's stack before calling it.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
[mpe: Drop 0x prefix to match most existings uses, especially xmon] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200602052728.18227-1-jniethe5@gmail.com
Jordan Niethe [Mon, 25 May 2020 02:59:23 +0000 (12:59 +1000)]
powerpc/sstep: Add tests for Prefixed Add Immediate
Use the existing support for testing compute type instructions to test
Prefixed Add Immediate (paddi). The R bit of the paddi instruction
controls whether current instruction address is used. Add test cases
for when R=1 and for R=0. paddi has a 34 bit immediate field formed by
concatenating si0 and si1. Add tests for the extreme values of this
field.
Skip the paddi tests if ISA v3.1 is unsupported.
Some of these test cases were added by Balamuruhan S.
Jordan Niethe [Mon, 25 May 2020 02:59:22 +0000 (12:59 +1000)]
powerpc/sstep: Let compute tests specify a required cpu feature
An a array of struct compute_test's are used to declare tests for
compute instructions. Add a cpu_feature field to struct compute_test as
an optional way to specify a cpu feature that must be present. If not
present then skip the test.
Jordan Niethe [Mon, 25 May 2020 02:59:21 +0000 (12:59 +1000)]
powerpc/sstep: Set NIP in instruction emulation tests
The tests for emulation of compute instructions execute and
emulate an instruction and then compare the results to verify the
emulation. In ISA v3.1 there are instructions that operate relative to
the NIP. Therefore set the NIP in the regs used for the emulated
instruction to the location of the executed instruction so they will
give the same result.
Jordan Niethe [Mon, 25 May 2020 02:59:20 +0000 (12:59 +1000)]
powerpc/sstep: Add tests for prefixed floating-point load/stores
Add tests for the prefixed versions of the floating-point load/stores
that are currently tested. This includes the following instructions:
* Prefixed Load Floating-Point Single (plfs)
* Prefixed Load Floating-Point Double (plfd)
* Prefixed Store Floating-Point Single (pstfs)
* Prefixed Store Floating-Point Double (pstfd)
Jordan Niethe [Mon, 25 May 2020 02:59:19 +0000 (12:59 +1000)]
powerpc/sstep: Add tests for prefixed integer load/stores
Add tests for the prefixed versions of the integer load/stores that
are currently tested. This includes the following instructions:
* Prefixed Load Doubleword (pld)
* Prefixed Load Word and Zero (plwz)
* Prefixed Store Doubleword (pstd)
Nicholas Piggin [Thu, 11 Jun 2020 08:12:03 +0000 (18:12 +1000)]
powerpc/64s: system call support for scv/rfscv instructions
Add support for the scv instruction on POWER9 and later CPUs.
For now this implements the zeroth scv vector 'scv 0', as identical to
'sc' system calls, with the exception that LR is not preserved, nor
are volatile CR registers, and error is not indicated with CR0[SO],
but by returning a negative errno.
rfscv is implemented to return from scv type system calls. It can not
be used to return from sc system calls because those are defined to
preserve LR.
getpid syscall throughput on POWER9 is improved by 26% (428 to 318
cycles), largely due to reducing mtmsr and mtspr.
Nicholas Piggin [Thu, 11 Jun 2020 08:12:02 +0000 (18:12 +1000)]
powerpc/64s/exception: treat NIA below __end_interrupts as soft-masked
The scv instruction causes an interrupt which can enter the kernel with
MSR[EE]=1, thus allowing interrupts to hit at any time. These must not
be taken as normal interrupts, because they come from MSR[PR]=0 context,
and yet the kernel stack is not yet set up and r13 is not set to the
PACA).
Treat this as a soft-masked interrupt regardless of the soft masked
state. This does not affect behaviour yet, because currently all
interrupts are taken with MSR[EE]=0.
powerpc/perf: BHRB control to disable BHRB logic when not used
PowerISA v3.1 has few updates for the Branch History Rolling
Buffer(BHRB).
BHRB disable is controlled via Monitor Mode Control Register A (MMCRA)
bit, namely "BHRB Recording Disable (BHRBRD)". This field controls
whether BHRB entries are written when BHRB recording is enabled by
other bits. This patch implements support for this BHRB disable bit.
By setting 0b1 to this bit will disable the BHRB and by setting 0b0 to
this bit will have BHRB enabled. This addresses backward
compatibility (for older OS), since this bit will be cleared and
hardware will be writing to BHRB by default.
This patch addresses changes to set MMCRA (BHRBRD) at boot for
power10 (there by the core will run faster) and enable this feature
only on runtime ie, on explicit need from user. Also save/restore
MMCRA in the restore path of state-loss idle state to make sure we
keep BHRB disabled if it was not enabled on request at runtime.
powerpc/perf: Add Power10 BHRB filter support for PERF_SAMPLE_BRANCH_IND_CALL/COND
PowerISA v3.1 introduce filtering support for
PERF_SAMPLE_BRANCH_IND_CALL/COND. The patch adds BHRB filter
support for "ind_call" and "cond" in power10_bhrb_filter_map().
powerpc/perf: Ignore the BHRB kernel address filtering for P10
Commit bb19af816025 ("powerpc/perf: Prevent kernel address leak to
userspace via BHRB buffer") added a check in bhrb_read() to filter
the kernel address from BHRB buffer. This patch modified it to avoid
that check for PowerISA v3.1 based processors, since PowerISA v3.1
allows only MSR[PR]=1 address to be written to BHRB buffer.
powerpc/perf: power10 Performance Monitoring support
Base enablement patch to register performance monitoring hardware
support for power10. Patch introduce the raw event encoding format,
defines the supported list of events, config fields for the event
attributes and their corresponding bit values which are exported via
sysfs.
Patch also enhances the support function in isa207_common.c to include
power10 pmu hardware.
powerpc/perf: Add Power10 PMU feature to DT CPU features
Add Power10 feature function to DT CPU features, along with a Power10
specific init() to initialize PMU SPRs, sets the oprofile_cpu_type and
cpu_features. This will enable performance monitoring unit (PMU) for
Power10 in CPU features with "performance-monitor-power10".
For Power ISA v3.1, BHRB disable is controlled via Monitor Mode
Control Register A (MMCRA) bit, namely "BHRB Recording
Disable (BHRBRD)". This patch initializes MMCRA BHRBRD to disable BHRB
feature at boot for Power10.
KVM: PPC: Book3S HV: Save/restore new PMU registers
Power ISA v3.1 has added new performance monitoring unit (PMU) special
purpose registers (SPRs). They are:
Monitor Mode Control Register 3 (MMCR3)
Sampled Instruction Event Register A (SIER2)
Sampled Instruction Event Register B (SIER3)
Add support to save/restore these new SPRs while entering/exiting
guest. Also include changes to support KVM_REG_PPC_MMCR3/SIER2/SIER3.
Add new SPRs to KVM API documentation.
MMCR3 is added for further sampling related configuration
control. SIER2/SIER3 are added to provide additional
information about the sampled instruction.
Patch adds new PPMU flag called "PPMU_ARCH_31" to support handling of
these new SPRs, updates the struct thread_struct to include these new
SPRs, include MMCR3 in struct mmcr_regs. This is needed to support
programming of MMCR3 SPR during event_enable/disable. Patch also adds
the sysfs support for the MMCR3 SPR along with SPRN_ macros for these
new pmu SPRs.
powerpc/perf: Update Power PMU cache_events to u64 type
Events of type PERF_TYPE_HW_CACHE was described for Power PMU
as: int (*cache_events)[type][op][result];
where type, op, result values unpacked from the event attribute config
value is used to generate the raw event code at runtime.
So far the event code values which used to create these cache-related
events were within 32 bit and `int` type worked. In power10,
some of the event codes are of 64-bit value and hence update the
Power PMU cache_events to `u64` type in `power_pmu` struct.
Also propagate this change to existing all PMU driver code paths
which are using ppmu->cache_events.
KVM: PPC: Book3S HV: Cleanup updates for kvm vcpu MMCR
Currently `kvm_vcpu_arch` stores all Monitor Mode Control registers
in a flat array in order: mmcr0, mmcr1, mmcra, mmcr2, mmcrs
Split this to give mmcra and mmcrs its own entries in vcpu and
use a flat array for mmcr0 to mmcr2. This patch implements this
cleanup to make code easier to read.
powerpc/perf: Update cpu_hw_event to use `struct` for storing MMCR registers
core-book3s currently uses array to store the MMCR registers as part
of per-cpu `cpu_hw_events`. This patch does a clean up to use `struct`
to store mmcr regs instead of array. This will make code easier to read
and reduces chance of any subtle bug that may come in the future, say
when new registers are added. Patch updates all relevant code that was
using MMCR array ( cpuhw->mmcr[x]) to use newly introduced `struct`.
This includes the PMU driver code for supported platforms (power5
to power9) and ISA macros for counter support functions.
Madhavan Srinivasan [Sun, 14 Jun 2020 08:36:04 +0000 (14:06 +0530)]
powerpc/perf: Fix missing is_sier_aviable() during build
Compilation error:
arch/powerpc/perf/perf_regs.c:80:undefined reference to `.is_sier_available'
Currently is_sier_available() is part of core-book3s.c, which is added
to build based on CONFIG_PPC_PERF_CTRS.
A config with CONFIG_PERF_EVENTS and without CONFIG_PPC_PERF_CTRS will
have a build break because of missing is_sier_available().
In practice it only breaks when CONFIG_FSL_EMB_PERF_EVENT=n because
that also guards the usage of is_sier_available(). That only happens
with CONFIG_PPC_BOOK3E_64=y and CONFIG_FSL_SOC_BOOKE=n.
Patch adds is_sier_available() in asm/perf_event.h to fix the build
break for configs missing CONFIG_PPC_PERF_CTRS.
Fixes: 333804dc3b7a ("powerpc/perf: Update perf_regs structure to include SIER") Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
[mpe: Add detail about CONFIG_FSL_SOC_BOOKE] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200614083604.302611-1-maddy@linux.ibm.com
Nicholas Piggin [Fri, 3 Jul 2020 01:19:58 +0000 (11:19 +1000)]
powerpc/64s/hash: Disable subpage_prot syscall by default
The subpage_prot syscall was added for specialised system software
(Lx86) that has been discontinued for about 7 years, and is not thought
to be used elsewhere, so disable it by default.
Nicholas Piggin [Fri, 3 Jul 2020 01:19:57 +0000 (11:19 +1000)]
powerpc/64s: Remove PROT_SAO support
ISA v3.1 does not support the SAO storage control attribute required to
implement PROT_SAO. PROT_SAO was used by specialised system software
(Lx86) that has been discontinued for about 7 years, and is not thought
to be used elsewhere, so removal should not cause problems.
We rather remove it than keep support for older processors, because
live migrating guest partitions to newer processors may not be possible
if SAO is in use (or worse allowed with silent races).
- PROT_SAO stays in the uapi header so code using it would still build.
- arch_validate_prot() is removed, the generic version rejects PROT_SAO
so applications would get a failure at mmap() time.
Alexander A. Klimov [Fri, 17 Jul 2020 18:29:40 +0000 (20:29 +0200)]
macintosh/therm_adt746x: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Alexander A. Klimov [Fri, 17 Jul 2020 18:35:22 +0000 (20:35 +0200)]
macintosh/adb: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Alexander A. Klimov [Sat, 18 Jul 2020 10:39:58 +0000 (12:39 +0200)]
powerpc: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
It's pretty clearly documented that fcheck() must be wrapped with
rcu_read_lock(), adding that fixes the RCU warning.
hch points out that once we've released the RCU read lock the file may
be closed and freed, which would leave us with a pointer to a freed
spu_context.
To avoid that, take a reference to the spu_context while we hold the
RCU read lock, and drop that reference later once we're done with the
context.
Michael Ellerman [Thu, 16 Jul 2020 12:21:42 +0000 (22:21 +1000)]
selftests/powerpc: Run per_event_excludes test on Power8 or later
The per_event_excludes test wants to run on Power8 or later. But
currently it checks that AT_BASE_PLATFORM *equals* power8, which means
it only runs on Power8.
Fix it to check for the ISA 2.07 feature, which will be set on Power8
and later CPUs.
There is only one caller to this function and the function is wrongly
named. Avoid further confusion w.r.t name and open code this at the
only call site. Also remove read_uamor(). There are no users for
the same after this.
selftests/powerpc: ptrace-pkey: Don't update expected UAMOR value
With commit 4a4a5e5d2aad ("powerpc/pkeys: key allocation/deallocation
must not change pkey registers") we are not updating UAMOR on key
allocation. So don't update the expected uamor value in the test.
powerpc/book3s64/kuap: Move UAMOR setup to key init function
UAMOR values are not application-specific. The kernel initializes
its value based on different reserved keys. Remove the thread-specific
UAMOR value and don't switch the UAMOR on context switch.
Move UAMOR initialization to key initialization code and remove
thread_struct.uamor because it is not used anymore.
Before commit: 4a4a5e5d2aad ("powerpc/pkeys: key allocation/deallocation must not change pkey registers")
we used to update uamor based on key allocation and free.
powerpc/book3s64/keys/kuap: Reset AMR/IAMR values on kexec
As we kexec across kernels that use AMR/IAMR for different purposes
we need to ensure that new kernels get kexec'd with a reset value
of AMR/IAMR. For ex: the new kernel can use key 0 for kernel mapping and the old
AMR value prevents access to key 0.
This patch also removes reset if IAMR and AMOR in kexec_sequence. Reset of AMOR
is not needed and the IAMR reset is partial (it doesn't do the reset
on secondary cpus) and is redundant with this patch.
powerpc/book3s64/pkeys: Mark all the pkeys above max pkey as reserved
The hypervisor can return less than max allowed pkey (for ex: 31) instead
of 32. We should mark all the pkeys above max allowed as reserved so
that we avoid the allocation of the wrong pkey(for ex: key 31 in the above
case) by userspace.
powerpc/book3s64/pkeys: Move pkey related bits in the linux page table
To keep things simple, all the pkey related bits are kept together
in linux page table for 64K config with hash translation. With hash-4k
kernel requires 4 bits to store slots details. This is done by overloading
some of the RPN bits for storing the slot details. Due to this PKEY_BIT0 on
the 4K config is used for storing hash slot details.
powerpc/book3s64/pkeys: Use PVR check instead of cpu feature
We are wrongly using CPU_FTRS_POWER8 to check for P8 support. Instead, we should
use PVR value. Now considering we are using CPU_FTRS_POWER8, that
implies we returned true for P9 with older firmware. Keep the same behavior
by checking for P9 PVR value.
Introduce notification chain which lets us know about uncorrected memory
errors(UE). This would help prospective users in pmem or nvdimm subsystem
to track bad blocks for better handling of persistent memory allocations.
powerpc/mm/radix: Create separate mappings for hot-plugged memory
To enable memory unplug without splitting kernel page table
mapping, we force the max mapping size to the LMB size. LMB
size is the unit in which hypervisor will do memory add/remove
operation.
Pseries systems supports max LMB size of 256MB. Hence on pseries,
we now end up mapping memory with 2M page size instead of 1G. To improve
that we want hypervisor to hint the kernel about the hotplug
memory range. That was added that as part of
commit b6eca183e23e ("powerpc/kernel: Enables memory
hot-remove after reboot on pseries guests")
But PowerVM doesn't provide that hint yet. Once we get PowerVM
updated, we can then force the 2M mapping only to hot-pluggable
memory region using memblock_is_hotpluggable(). Till then
let's depend on LMB size for finding the mapping page size
for linear range.
With this change KVM guest will also be doing linear mapping with
2M page size.
The actual TLB benefit of mapping guest page table entries with
hugepage size can only be materialized if the partition scoped
entries are also using the same or higher page size. A guest using
1G hugetlbfs backing guest memory can have a performance impact with
the above change.
Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Fold in fix from Aneesh spotted by lkp@intel.com] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709131925.922266-5-aneesh.kumar@linux.ibm.com
We split the page table mapping on memory unplug if the
linear range was mapped with huge page mapping (for ex: 1G)
The page table splitting code has a few issues:
1. Recursive locking
--------------------
Memory unplug path takes cpu_hotplug_lock and calls stop_machine()
for splitting the mappings. However stop_machine() takes
cpu_hotplug_lock again causing deadlock.
2. BUG: sleeping function called from in_atomic() context
---------------------------------------------------------
Memory unplug path (remove_pagetable) takes init_mm.page_table_lock
spinlock and later calls stop_machine() which does wait_for_completion()
3. Bad unlock unbalance
-----------------------
Memory unplug path takes init_mm.page_table_lock spinlock and calls
stop_machine(). The stop_machine thread function runs in a different
thread context (migration thread) which tries to release and reaquire
ptl. Releasing ptl from a different thread than which acquired it
causes bad unlock unbalance.
These problems can be avoided if we avoid mapping hot-plugged memory
with 1G mapping, thereby removing the need for splitting them during
unplug. The kernel always make sure the minimum unplug request is
SUBSECTION_SIZE for device memory and SECTION_SIZE for regular memory.
In preparation for such a change remove page table splitting support.
This essentially is a revert of
commit 4dd5f8a99e791 ("powerpc/mm/radix: Split linear mapping on hot-unplug")
powerpc/mm/radix: Fix PTE/PMD fragment count for early page table mappings
We can hit the following BUG_ON during memory unplug:
kernel BUG at arch/powerpc/mm/book3s64/pgtable.c:342!
Oops: Exception in kernel mode, sig: 5 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
NIP [c000000000093308] pmd_fragment_free+0x48/0xc0
LR [c00000000147bfec] remove_pagetable+0x578/0x60c
Call Trace:
0xc000008050000000 (unreliable)
remove_pagetable+0x384/0x60c
radix__remove_section_mapping+0x18/0x2c
remove_section_mapping+0x1c/0x3c
arch_remove_memory+0x11c/0x180
try_remove_memory+0x120/0x1b0
__remove_memory+0x20/0x40
dlpar_remove_lmb+0xc0/0x114
dlpar_memory+0x8b0/0xb20
handle_dlpar_errorlog+0xc0/0x190
pseries_hp_work_fn+0x2c/0x60
process_one_work+0x30c/0x810
worker_thread+0x98/0x540
kthread+0x1c4/0x1d0
ret_from_kernel_thread+0x5c/0x74
This occurs when unplug is attempted for such memory which has
been mapped using memblock pages as part of early kernel page
table setup. We wouldn't have initialized the PMD or PTE fragment
count for those PMD or PTE pages.
This can be fixed by allocating memory in PAGE_SIZE granularity
during early page table allocation. This makes sure a specific
page is not shared for another memblock allocation and we can
free them correctly on removing page-table pages.
Since we now do PAGE_SIZE allocations for both PUD table and
PMD table (Note that PTE table allocation is already of PAGE_SIZE),
we end up allocating more memory for the same amount of system RAM.
Here is a comparision of how much more we need for a 64T and 2G
system after this patch:
1. 64T system
-------------
64T RAM would need 64G for vmemmap with struct page size being 64B.
128 PUD tables for 64T memory (1G mappings)
1 PUD table and 64 PMD tables for 64G vmemmap (2M mappings)
With default PUD[PMD]_TABLE_SIZE(4K), (128+1+64)*4K=772K
With PAGE_SIZE(64K) table allocations, (128+1+64)*64K=12352K
2. 2G system
------------
2G RAM would need 2M for vmemmap with struct page size being 64B.
1 PUD table for 2G memory (1G mapping)
1 PUD table and 1 PMD table for 2M vmemmap (2M mappings)
With default PUD[PMD]_TABLE_SIZE(4K), (1+1+1)*4K=12K
With new PAGE_SIZE(64K) table allocations, (1+1+1)*64K=192K
Nicholas Piggin [Mon, 20 Jul 2020 04:42:58 +0000 (10:12 +0530)]
powerpc/prom: Enable Radix GTSE in cpu pa-features
When '029ab30b4c0a ("powerpc/mm: Enable radix GTSE only if supported.")'
made GTSE an MMU feature, it was enabled by default in
powerpc-cpu-features but was missed in pa-features. This causes random
memory corruption during boot of PowerNV kernels where
CONFIG_PPC_DT_CPU_FTRS isn't enabled.
Fixes: 029ab30b4c0a ("powerpc/mm: Enable radix GTSE only if supported.") Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
[mpe: Unwrap long line] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200720044258.863574-1-bharata@linux.ibm.com
powerpc/pseries: Detect secure and trusted boot state of the system.
The device-tree properties to check secure and trusted boot state are
different for guests (pseries) compared to baremetal (powernv).
This patch updates the existing is_ppc_secureboot_enabled() and
is_ppc_trustedboot_enabled() functions to add support for pseries.
For pseries the secureboot and trustedboot state are exposed via
device-tree properties /ibm,secure-boot and /ibm,trusted-boot.
The values of ibm,secure-boot under pseries are interpreted as:
0 - Disabled
1 - Enabled in Log-only mode. This patch interprets this value as
disabled, since audit mode is currently not supported for
Linux.
2 - Enabled and enforced.
3-9 - Enabled and enforcing; requirements are at the discretion of
the operating system.
The values of ibm,trusted-boot under pseries are interpreted as:
0 - Disabled
1 - Enabled
Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
[mpe: Drop machdep.h inclusion, tweak change log slightly] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1594813921-12425-1-git-send-email-nayna@linux.ibm.com
Milton Miller [Wed, 15 Jul 2020 23:37:04 +0000 (09:37 +1000)]
powerpc/vdso: Fix vdso cpu truncation
The code in vdso_cpu_init that exposes the cpu and numa node to
userspace via SPRG_VDSO incorrctly masks the cpu to 12 bits. This means
that any kernel running on a box with more than 4096 threads (NR_CPUS
advertises a limit of of 8192 cpus) would expose userspace to two cpu
contexts running at the same time with the same cpu number.
Note: I'm not aware of any distro shipping a kernel with support for more
than 4096 threads today, nor of any system image that currently exceeds
4096 threads. Found via code browsing.
Fixes: 18ad51dd342a7eb09dbcd059d0b451b616d4dafc ("powerpc: Add VDSO version of getcpu") Signed-off-by: Milton Miller <miltonm@us.ibm.com> Signed-off-by: Anton Blanchard <anton@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200715233704.1352257-1-anton@ozlabs.org
powerpc/perf: Add kernel support for new MSR[HV PR] bits in trace-imc
IMC trace-mode record has MSR[HV PR] bits added in the third DW.
These bits can be used to set the cpumode for the instruction pointer
captured in each sample.
Add support in kernel to use these bits to set the cpumode for
each sample.
Alexander A. Klimov [Mon, 13 Jul 2020 19:26:56 +0000 (21:26 +0200)]
powerpc/Kconfig: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Alexander A. Klimov [Mon, 13 Jul 2020 17:55:06 +0000 (19:55 +0200)]
ocxl: Replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
powerpc/fadump: fix race between pstore write and fadump crash trigger
When we enter into fadump crash path via system reset we fail to update
the pstore.
On the system reset path we first update the pstore then we go for fadump
crash. But the problem here is when all the CPUs try to get the pstore
lock to initiate the pstore write, only one CPUs will acquire the lock
and proceed with the pstore write. Since it in NMI context CPUs that fail
to get lock do not wait for their turn to write to the pstore and simply
proceed with the next operation which is fadump crash. One of the CPU who
proceeded with fadump crash path triggers the crash and does not wait for
the CPU who gets the pstore lock to complete the pstore update.
Timeline diagram to depicts the sequence of events that leads to an
unsuccessful pstore update when we hit fadump crash path via system reset.
1 2 3 ... n CPU Threads
| | | |
| | | |
Reached to -->|--->|---->| ----------->|
system reset | | | |
path | | | |
| | | |
Try to -->|--->|---->|------------>|
acquire the | | | |
pstore lock | | | |
| | | |
| | | |
Got the -->| +->| | |<-+
pstore lock | | | | | |--> Didn't get the
| --------------------------+ lock and moving
| | | | ahead on fadump
| | | | crash path
| | | |
Begins the -->| | | |
process to | | | |<-- Got the chance to
update the | | | | trigger the crash
pstore | -> | | ... <- |
| | | | | |
| | | | | |<-- Triggers the
| | | | | | crash
| | | | | | ^
| | | | | | |
Writing to -->| | | | | | |
pstore | | | | | | |
| | |
^ |__________________| |
| CPU Relax |
| |
+-----------------------------------------+
|
v
Race: crash triggered before pstore
update completes
To avoid this race condition a barrier is added on crash_fadump path, it
prevents the CPU to trigger the crash until all the online CPUs completes
their task.
A barrier is added to make sure all the secondary CPUs hit the
crash_fadump function before we initiates the crash. A timeout is kept to
ensure the primary CPU (one who initiates the crash) do not wait for
secondary CPUs indefinitely.
Anton Blanchard [Mon, 13 Jul 2020 08:36:01 +0000 (18:36 +1000)]
powerpc: Add cputime_to_nsecs()
Generic code has a wrapper to implement cputime_to_nsecs() on top of
cputime_to_usecs() but we can easily return the full nanosecond
resolution directly.