Age | Commit message (Collapse) | Author |
|
Preempt should be consistently disabled for mm_is_thread_local tests,
so bring the rest of these under preempt_disable().
Preempt does not need to be disabled for the mm->context.id tests,
which allows simplification and removal of gotos.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Close the recoverability gap for OPAL calls by using FIXUP_ENDIAN_HV
in the return path.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Add an HV variant of FIXUP_ENDIAN which uses HSRR[01] and does not
clear MSR[RI], which improves recoverability.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
When returning from an exception to a soft-enabled context, pending
IRQs are replayed but IRQ tracing is not reset, so a number of them
can get chained together into the same IRQ-disabled trace.
Fix this by having __check_irq_replay re-set IRQ trace. This is
conceptually where we respond to the next interrupt, so it fits the
semantics of the IRQ tracer.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
If the host takes a system reset interrupt while a guest is running,
the CPU must exit the guest before processing the host exception
handler.
After this patch, taking a sysrq+x with a CPU running in a guest
gives a trace like this:
cpu 0x27: Vector: 100 (System Reset) at [c000000fdf5776f0]
pc: c008000010158b80: kvmppc_run_core+0x16b8/0x1ad0 [kvm_hv]
lr: c008000010158b80: kvmppc_run_core+0x16b8/0x1ad0 [kvm_hv]
sp: c000000fdf577850
msr: 9000000002803033
current = 0xc000000fdf4b1e00
paca = 0xc00000000fd4d680 softe: 3 irq_happened: 0x01
pid = 6608, comm = qemu-system-ppc
Linux version 4.14.0-rc7-01489-g47e1893a404a-dirty #26 SMP
[c000000fdf577a00] c008000010159dd4 kvmppc_vcpu_run_hv+0x3dc/0x12d0 [kvm_hv]
[c000000fdf577b30] c0080000100a537c kvmppc_vcpu_run+0x44/0x60 [kvm]
[c000000fdf577b60] c0080000100a1ae0 kvm_arch_vcpu_ioctl_run+0x118/0x310 [kvm]
[c000000fdf577c00] c008000010093e98 kvm_vcpu_ioctl+0x530/0x7c0 [kvm]
[c000000fdf577d50] c000000000357bf8 do_vfs_ioctl+0xd8/0x8c0
[c000000fdf577df0] c000000000358448 SyS_ioctl+0x68/0x100
[c000000fdf577e30] c00000000000b220 system_call+0x58/0x6c
--- Exception: c01 (System Call) at 00007fff76868df0
SP (7fff7069baf0) is in userspace
Fixes: e36d0a2ed5 ("powerpc/powernv: Implement NMI IPI with OPAL_SIGNAL_SYSTEM_RESET")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Some more powerpc fixes for 4.14.
This is bigger than I like to send at rc7, but that's at least partly
because I didn't send any fixes last week. If it wasn't for the IMC
driver, which is new and getting heavy testing, the diffstat would
look a bit better. I've also added ftrace on big endian to my test
suite, so we shouldn't break that again in future.
- A fix to the handling of misaligned paste instructions (P9 only),
where a change to a #define has caused the check for the
instruction to always fail.
- The preempt handling was unbalanced in the radix THP flush (P9
only). Though we don't generally use preempt we want to keep it
working as much as possible.
- Two fixes for IMC (P9 only), one when booting with restricted
number of CPUs and one in the error handling when initialisation
fails due to firmware etc.
- A revert to fix function_graph on big endian machines, and then a
rework of the reverted patch to fix kprobes blacklist handling on
big endian machines.
Thanks to: Anju T Sudhakar, Guilherme G. Piccoli, Madhavan Srinivasan,
Naveen N. Rao, Nicholas Piggin, Paul Mackerras"
* tag 'powerpc-4.14-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/perf: Fix core-imc hotplug callback failure during imc initialization
powerpc/kprobes: Dereference function pointers only if the address does not belong to kernel text
Revert "powerpc64/elfv1: Only dereference function descriptor for non-text symbols"
powerpc/64s/radix: Fix preempt imbalance in TLB flush
powerpc: Fix check for copy/paste instructions in alignment handler
powerpc/perf: Fix IMC allocation routine
|
|
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Kees Cook <keescook@chromium.org>
|
|
Call trace observed during boot:
nest_capp0_imc performance monitor hardware support registered
nest_capp1_imc performance monitor hardware support registered
core_imc memory allocation for cpu 56 failed
Unable to handle kernel paging request for data at address 0xffa400010
Faulting instruction address: 0xc000000000bf3294
0:mon> e
cpu 0x0: Vector: 300 (Data Access) at [c000000ff38ff8d0]
pc: c000000000bf3294: mutex_lock+0x34/0x90
lr: c000000000bf3288: mutex_lock+0x28/0x90
sp: c000000ff38ffb50
msr: 9000000002009033
dar: ffa400010
dsisr: 80000
current = 0xc000000ff383de00
paca = 0xc000000007ae0000 softe: 0 irq_happened: 0x01
pid = 13, comm = cpuhp/0
Linux version 4.11.0-39.el7a.ppc64le (mockbuild@ppc-058.build.eng.bos.redhat.com) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-16) (GCC) ) #1 SMP Tue Oct 3 07:42:44 EDT 2017
0:mon> t
[c000000ff38ffb80] c0000000002ddfac perf_pmu_migrate_context+0xac/0x470
[c000000ff38ffc40] c00000000011385c ppc_core_imc_cpu_offline+0x1ac/0x1e0
[c000000ff38ffc90] c000000000125758 cpuhp_invoke_callback+0x198/0x5d0
[c000000ff38ffd00] c00000000012782c cpuhp_thread_fun+0x8c/0x3d0
[c000000ff38ffd60] c0000000001678d0 smpboot_thread_fn+0x290/0x2a0
[c000000ff38ffdc0] c00000000015ee78 kthread+0x168/0x1b0
[c000000ff38ffe30] c00000000000b368 ret_from_kernel_thread+0x5c/0x74
While registering the cpuhoplug callbacks for core-imc, if we fails
in the cpuhotplug online path for any random core (either because opal call to
initialize the core-imc counters fails or because memory allocation fails for
that core), ppc_core_imc_cpu_offline() will get invoked for other cpus who
successfully returned from cpuhotplug online path.
But in the ppc_core_imc_cpu_offline() path we are trying to migrate the event
context, when core-imc counters are not even initialized. Thus creating the
above stack dump.
Add a check to see if core-imc counters are enabled or not in the cpuhotplug
offline path before migrating the context to handle this failing scenario.
Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support")
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull initial SPDX identifiers from Greg KH:
"License cleanup: add SPDX license identifiers to some files
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the
'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally
binding shorthand, which can be used instead of the full boiler plate
text.
This patch is based on work done by Thomas Gleixner and Kate Stewart
and Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset
of the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to
license had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied
to a file was done in a spreadsheet of side by side results from of
the output of two independent scanners (ScanCode & Windriver)
producing SPDX tag:value files created by Philippe Ombredanne.
Philippe prepared the base worksheet, and did an initial spot review
of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537
files assessed. Kate Stewart did a file by file comparison of the
scanner results in the spreadsheet to determine which SPDX license
identifier(s) to be applied to the file. She confirmed any
determination that was not immediately clear with lawyers working with
the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained
>5 lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that
was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that
became the concluded license(s).
- when there was disagreement between the two scanners (one detected
a license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply
(and which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases,
confirmation by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.
The Windriver scanner is based on an older version of FOSSology in
part, so they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot
checks in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect
the correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial
patch version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch
license was not GPL-2.0 WITH Linux-syscall-note to ensure that the
applied SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
License cleanup: add SPDX license identifier to uapi header files with a license
License cleanup: add SPDX license identifier to uapi header files with no license
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
|
|
Many user space API headers have licensing information, which is either
incomplete, badly formatted or just a shorthand for referring to the
license under which the file is supposed to be. This makes it hard for
compliance tools to determine the correct license.
Update these files with an SPDX license identifier. The identifier was
chosen based on the license information in the file.
GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license
identifier with the added 'WITH Linux-syscall-note' exception, which is
the officially assigned exception identifier for the kernel syscall
exception:
NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".
This exception makes it possible to include GPL headers into non GPL
code, without confusing license compliance tools.
Headers which have either explicit dual licensing or are just licensed
under a non GPL license are updated with the corresponding SPDX
identifier and the GPLv2 with syscall exception identifier. The format
is:
((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE)
SPDX license identifiers are a legally binding shorthand, which can be
used instead of the full boiler plate text. The update does not remove
existing license information as this has to be done on a case by case
basis and the copyright holders might have to be consulted. This will
happen in a separate step.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne. See the previous patch in this series for the
methodology of how this patch was researched.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
license
Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.
By default are files without license information under the default
license of the kernel, which is GPLV2. Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:
NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".
otherwise syscall usage would not be possible.
Update the files which contain no license information with an SPDX
license identifier. The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception. SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne. See the previous patch in this series for the
methodology of how this patch was researched.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Linux 4.14-rc7
Requested by Ben Skeggs for nouveau to avoid major conflicts,
and things were getting a bit conflicty already, esp around amdgpu
reverts.
|
|
belong to kernel text
This makes the changes introduced in commit 83e840c770f2c5
("powerpc64/elfv1: Only dereference function descriptor for non-text
symbols") to be specific to the kprobe subsystem.
We previously changed ppc_function_entry() to always check the provided
address to confirm if it needed to be dereferenced. This is actually
only an issue for kprobe blacklisted asm labels (through use of
_ASM_NOKPROBE_SYMBOL) and can cause other issues with ftrace. Also, the
additional checks are not really necessary for our other uses.
As such, move this check to the kprobes subsystem.
Fixes: 83e840c770f2 ("powerpc64/elfv1: Only dereference function descriptor for non-text symbols")
Cc: stable@vger.kernel.org # v4.13+
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
symbols"
This reverts commit 83e840c770f2c5 ("powerpc64/elfv1: Only dereference
function descriptor for non-text symbols").
Chandan reported that on newer kernels, trying to enable function_graph
tracer on ppc64 (BE) locks up the system with the following trace:
Unable to handle kernel paging request for data at address 0x600000002fa30010
Faulting instruction address: 0xc0000000001f1300
Thread overran stack, or stack corrupted
Oops: Kernel access of bad area, sig: 11 [#1]
BE SMP NR_CPUS=2048 DEBUG_PAGEALLOC NUMA pSeries
Modules linked in:
CPU: 1 PID: 6586 Comm: bash Not tainted 4.14.0-rc3-00162-g6e51f1f-dirty #20
task: c000000625c07200 task.stack: c000000625c07310
NIP: c0000000001f1300 LR: c000000000121cac CTR: c000000000061af8
REGS: c000000625c088c0 TRAP: 0380 Not tainted (4.14.0-rc3-00162-g6e51f1f-dirty)
MSR: 8000000000001032 <SF,ME,IR,DR,RI> CR: 28002848 XER: 00000000
CFAR: c0000000001f1320 SOFTE: 0
...
NIP [c0000000001f1300] .__is_insn_slot_addr+0x30/0x90
LR [c000000000121cac] .kernel_text_address+0x18c/0x1c0
Call Trace:
[c000000625c08b40] [c0000000001bd040] .is_module_text_address+0x20/0x40 (unreliable)
[c000000625c08bc0] [c000000000121cac] .kernel_text_address+0x18c/0x1c0
[c000000625c08c50] [c000000000061960] .prepare_ftrace_return+0x50/0x130
[c000000625c08cf0] [c000000000061b10] .ftrace_graph_caller+0x14/0x34
[c000000625c08d60] [c000000000121b40] .kernel_text_address+0x20/0x1c0
[c000000625c08df0] [c000000000061960] .prepare_ftrace_return+0x50/0x130
...
[c000000625c0ab30] [c000000000061960] .prepare_ftrace_return+0x50/0x130
[c000000625c0abd0] [c000000000061b10] .ftrace_graph_caller+0x14/0x34
[c000000625c0ac40] [c000000000121b40] .kernel_text_address+0x20/0x1c0
[c000000625c0acd0] [c000000000061960] .prepare_ftrace_return+0x50/0x130
[c000000625c0ad70] [c000000000061b10] .ftrace_graph_caller+0x14/0x34
[c000000625c0ade0] [c000000000121b40] .kernel_text_address+0x20/0x1c0
This is because ftrace is using ppc_function_entry() for obtaining the
address of return_to_handler() in prepare_ftrace_return(). The call to
kernel_text_address() itself gets traced and we end up in a recursive
loop.
Fixes: 83e840c770f2 ("powerpc64/elfv1: Only dereference function descriptor for non-text symbols")
Cc: stable@vger.kernel.org # v4.13+
Reported-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
This patch removes the restriction that a radix host can only run
radix guests, allowing us to run HPT (hashed page table) guests as
well. This is useful because it provides a way to run old guest
kernels that know about POWER8 but not POWER9.
Unfortunately, POWER9 currently has a restriction that all threads
in a given code must either all be in HPT mode, or all in radix mode.
This means that when entering a HPT guest, we have to obtain control
of all 4 threads in the core and get them to switch their LPIDR and
LPCR registers, even if they are not going to run a guest. On guest
exit we also have to get all threads to switch LPIDR and LPCR back
to host values.
To make this feasible, we require that KVM not be in the "independent
threads" mode, and that the CPU cores be in single-threaded mode from
the host kernel's perspective (only thread 0 online; threads 1, 2 and
3 offline). That allows us to use the same code as on POWER8 for
obtaining control of the secondary threads.
To manage the LPCR/LPIDR changes required, we extend the kvm_split_info
struct to contain the information needed by the secondary threads.
All threads perform a barrier synchronization (where all threads wait
for every other thread to reach the synchronization point) on guest
entry, both before and after loading LPCR and LPIDR. On guest exit,
they all once again perform a barrier synchronization both before
and after loading host values into LPCR and LPIDR.
Finally, it is also currently necessary to flush the entire TLB every
time we enter a HPT guest on a radix host. We do this on thread 0
with a loop of tlbiel instructions.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This patch allows for a mode on POWER9 hosts where we control all the
threads of a core, much as we do on POWER8. The mode is controlled by
a module parameter on the kvm_hv module, called "indep_threads_mode".
The normal mode on POWER9 is the "independent threads" mode, with
indep_threads_mode=Y, where the host is in SMT4 mode (or in fact any
desired SMT mode) and each thread independently enters and exits from
KVM guests without reference to what other threads in the core are
doing.
If indep_threads_mode is set to N at the point when a VM is started,
KVM will expect every core that the guest runs on to be in single
threaded mode (that is, threads 1, 2 and 3 offline), and will set the
flag that prevents secondary threads from coming online. We can still
use all four threads; the code that implements dynamic micro-threading
on POWER8 will become active in over-commit situations and will allow
up to three other VCPUs to be run on the secondary threads of the core
whenever a VCPU is run.
The reason for wanting this mode is that this will allow us to run HPT
guests on a radix host on a POWER9 machine that does not support
"mixed mode", that is, having some threads in a core be in HPT mode
while other threads are in radix mode. It will also make it possible
to implement a "strict threads" mode in future, if desired.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This sets up the machinery for switching a guest between HPT (hashed
page table) and radix MMU modes, so that in future we can run a HPT
guest on a radix host on POWER9 machines.
* The KVM_PPC_CONFIGURE_V3_MMU ioctl can now specify either HPT or
radix mode, on a radix host.
* The KVM_CAP_PPC_MMU_HASH_V3 capability now returns 1 on POWER9
with HV KVM on a radix host.
* The KVM_PPC_GET_SMMU_INFO returns information about the HPT MMU on a
radix host.
* The KVM_PPC_ALLOCATE_HTAB ioctl on a radix host will switch the
guest to HPT mode and allocate a HPT.
* For simplicity, we now allocate the rmap array for each memslot,
even on a radix host, since it will be needed if the guest switches
to HPT mode.
* Since we cannot yet run a HPT guest on a radix host, the KVM_RUN
ioctl will return an EINVAL error in that case.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Currently, the HPT code in HV KVM maintains a dirty bit per guest page
in the rmap array, whether or not dirty page tracking has been enabled
for the memory slot. In contrast, the radix code maintains a dirty
bit per guest page in memslot->dirty_bitmap, and only does so when
dirty page tracking has been enabled.
This changes the HPT code to maintain the dirty bits in the memslot
dirty_bitmap like radix does. This results in slightly less code
overall, and will mean that we do not lose the dirty bits when
transitioning between HPT and radix mode in future.
There is one minor change to behaviour as a result. With HPT, when
dirty tracking was enabled for a memslot, we would previously clear
all the dirty bits at that point (both in the HPT entries and in the
rmap arrays), meaning that a KVM_GET_DIRTY_LOG ioctl immediately
following would show no pages as dirty (assuming no vcpus have run
in the meantime). With this change, the dirty bits on HPT entries
are not cleared at the point where dirty tracking is enabled, so
KVM_GET_DIRTY_LOG would show as dirty any guest pages that are
resident in the HPT and dirty. This is consistent with what happens
on radix.
This also fixes a bug in the mark_pages_dirty() function for radix
(in the sense that the function no longer exists). In the case where
a large page of 64 normal pages or more is marked dirty, the
addressing of the dirty bitmap was incorrect and could write past
the end of the bitmap. Fortunately this case was never hit in
practice because a 2MB large page is only 32 x 64kB pages, and we
don't support backing the guest with 1GB huge pages at this point.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This renames the kvm->arch.hpte_setup_done field to mmu_ready because
we will want to use it for radix guests too -- both for setting things
up before vcpu execution, and for excluding vcpus from executing while
MMU-related things get changed, such as in future switching the MMU
from radix to HPT mode or vice-versa.
This also moves the call to kvmppc_setup_partition_table() that was
done in kvmppc_hv_setup_htab_rma() for HPT guests, and the setting
of mmu_ready, into the caller in kvmppc_vcpu_run_hv().
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This removes the dependence of KVM on the mmu_psize_defs array (which
stores information about hardware support for various page sizes) and
the things derived from it, chiefly hpte_page_sizes[], hpte_page_size(),
hpte_actual_page_size() and get_sllp_encoding(). We also no longer
rely on the mmu_slb_size variable or the MMU_FTR_1T_SEGMENTS feature
bit.
The reason for doing this is so we can support a HPT guest on a radix
host. In a radix host, the mmu_psize_defs array contains information
about page sizes supported by the MMU in radix mode rather than the
page sizes supported by the MMU in HPT mode. Similarly, mmu_slb_size
and the MMU_FTR_1T_SEGMENTS bit are not set.
Instead we hard-code knowledge of the behaviour of the HPT MMU in the
POWER7, POWER8 and POWER9 processors (which are the only processors
supported by HV KVM) - specifically the encoding of the LP fields in
the HPT and SLB entries, and the fact that they have 32 SLB entries
and support 1TB segments.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This merges in the ppc-kvm topic branch of the powerpc tree to get the
commit that reverts the patch "KVM: PPC: Book3S HV: POWER9 does not
require secondary thread management". This is needed for subsequent
patches which will be applied on this branch.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This fixes the message:
arch/powerpc/kvm/book3s_segment.S: Assembler messages:
arch/powerpc/kvm/book3s_segment.S:330: Warning: invalid register expression
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Userland passes an array of 64 SLB descriptors to KVM_SET_SREGS,
some of which are valid (ie, SLB_ESID_V is set) and the rest are
likely all-zeroes (with QEMU at least).
Each of them is then passed to kvmppc_mmu_book3s_64_slbmte(), which
assumes to find the SLB index in the 3 lower bits of its rb argument.
When passed zeroed arguments, it happily overwrites the 0th SLB entry
with zeroes. This is exactly what happens while doing live migration
with QEMU when the destination pushes the incoming SLB descriptors to
KVM PR. When reloading the SLBs at the next synchronization, QEMU first
clears its SLB array and only restore valid ones, but the 0th one is
now gone and we cannot access the corresponding memory anymore:
(qemu) x/x $pc
c0000000000b742c: Cannot access memory
To avoid this, let's filter out non-valid SLB entries. While here, we
also force a full SLB flush before installing new entries. Since SLB
is for 64-bit only, we now build this path conditionally to avoid a
build break on 32-bit, which doesn't define SLB_ESID_V.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
When running a guest on a POWER9 system with the in-kernel XICS
emulation disabled (for example by running QEMU with the parameter
"-machine pseries,kernel_irqchip=off"), the kernel does not pass
the XICS-related hypercalls such as H_CPPR up to userspace for
emulation there as it should.
The reason for this is that the real-mode handlers for these
hypercalls don't check whether a XICS device has been instantiated
before calling the xics-on-xive code. That code doesn't check
either, leading to potential NULL pointer dereferences because
vcpu->arch.xive_vcpu is NULL. Those dereferences won't cause an
exception in real mode but will lead to kernel memory corruption.
This fixes it by adding kvmppc_xics_enabled() checks before calling
the XICS functions.
Cc: stable@vger.kernel.org # v4.11+
Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Several function prototypes for the set/get functions defined by
module_param_call() have a slightly wrong argument types. This fixes
those in an effort to clean up the calls when running under type-enforced
compiler instrumentation for CFI. This is the result of running the
following semantic patch:
@match_module_param_call_function@
declarer name module_param_call;
identifier _name, _set_func, _get_func;
expression _arg, _mode;
@@
module_param_call(_name, _set_func, _get_func, _arg, _mode);
@fix_set_prototype
depends on match_module_param_call_function@
identifier match_module_param_call_function._set_func;
identifier _val, _param;
type _val_type, _param_type;
@@
int _set_func(
-_val_type _val
+const char * _val
,
-_param_type _param
+const struct kernel_param * _param
) { ... }
@fix_get_prototype
depends on match_module_param_call_function@
identifier match_module_param_call_function._get_func;
identifier _val, _param;
type _val_type, _param_type;
@@
int _get_func(
-_val_type _val
+char * _val
,
-_param_type _param
+const struct kernel_param * _param
) { ... }
Two additional by-hand changes are included for places where the above
Coccinelle script didn't notice them:
drivers/platform/x86/thinkpad_acpi.c
fs/lockd/svc.c
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
|
|
Fixes: 424de9c6e3f8 ("powerpc/mm/radix: Avoid flushing the PWC on every flush_tlb_range")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Commit 07d2a628bc00 ("powerpc/64s: Avoid cpabort in context switch
when possible", 2017-06-09) changed the definition of PPC_INST_COPY
and in so doing inadvertently broke the check for copy/paste
instructions in the alignment fault handler. The check currently
matches no instructions.
This fixes it by ANDing both sides of the comparison with the mask.
Fixes: 07d2a628bc00 ("powerpc/64s: Avoid cpabort in context switch when possible")
Cc: stable@vger.kernel.org # v4.13+
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
When setting nr_cpus=1, we observed a crash in IMC code during boot
due to a missing allocation: basically, IMC code is taking the number
of threads into account in imc_mem_init() and if we manually set
nr_cpus for a value that is not multiple of the number of threads per
core, an integer division in that function will discard the decimal
portion, leading IMC to not allocate one mem_info struct. This causes
a NULL pointer dereference later, on is_core_imc_mem_inited().
This patch just rounds that division up, fixing the bug.
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Acked-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
to READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Although kfree(NULL) is legal, it's a bit lazy to rely on that to
implement the error handling. So do it the normal Linux way using
labels for each failure path.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[mpe: Squash a few patches and rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Fix a word in these descriptions.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
The local variable "rc" will eventually be set only to an error code.
Thus omit the explicit initialisation at the beginning.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
In the hv-24x7 code there is a function memord() which tries to
implement a sort function return -1, 0, 1. However one of the
conditions is incorrect, such that it can never be true, because we
will have already returned.
I don't believe there is a bug in practice though, because the
comparisons are an optimisation prior to calling memcmp().
Fix it by swapping the second comparision, so it can be true.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Back in 2008 we added support for "fast little-endian switch" in the
syscall path. This added a special case syscall number 0x1ebe, which
is caught very early in the system call exception and switches endian
with as little overhead as possible. See commit 745a14cc264b
("[POWERPC] Add fast little-endian switch system call") for full
details.
Although it is fast, it's also completely non standard. The "syscall
number" is out of the range of normal syscalls, it can't be traced or
audited, and it's a bit of a wart. To the best of our knowledge it was
only used by one program, now long since discontinued.
So in an effort to shake out any current users, put it behind a config
option, and make it default n. If anyone *is* using it they can
quickly reinstate it with a rebuild, and we can flip it to default y.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
So we can #ifdef them in the next patch.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
When dumping the paca in xmon we currently show kstack. Although it's
not hard it's a bit fiddly to work out what the bounds of the kernel
stack should be based on the kstack value.
To make life easier and "kstack_base" which is the base (lowest
address) of the kernel stack, eg:
kstack = 0xc0000000f1a7be30 (0x258)
kstack_base = 0xc0000000f1a78000
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
i2c-dev provides an interface for userspace programs to interact with I2C
devices, and is very helpful for I2C-related debugging.
Enable it in pseries_defconfig and powernv_defconfig. It's already enabled
in many other powerpc defconfigs.
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
We call these functions with non-NULL mm or vma. Hence we can skip the
NULL check in these functions. We also remove now unused function
__local_flush_hugetlb_page().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Drop the checks with is_vm_hugetlb_page() as noticed by Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Currently xmon could call XIVE functions from OPAL even if the XIVE is
disabled or does not exist in the system, as in POWER8 machines. This
causes the following exception:
1:mon> dx
cpu 0x1: Vector: 700 (Program Check) at [c000000423c93450]
pc: c00000000009cfa4: opal_xive_dump+0x50/0x68
lr: c0000000000997b8: opal_return+0x0/0x50
This patch simply checks if XIVE is enabled before calling XIVE
functions.
Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Suggested-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Unfortunately userspace can construct a sigcontext which enables
suspend. Thus userspace can force Linux into a path where trechkpt is
executed.
This patch blocks this from happening on POWER9 by sanity checking
sigcontexts passed in.
ptrace doesn't have this problem as only MSR SE and BE can be changed
via ptrace.
This patch also adds a number of WARN_ON()s in case we ever enter
suspend when we shouldn't. This should not happen, but if it does the
symptoms are soft lockup warnings which are not obviously TM related,
so the WARN_ON()s should make it obvious what's happening.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Some Power9 revisions can run in a mode where TM operates without
suspended state. If we find ourself on a CPU that might be in this
mode, we query OPAL to check, and if so we reenable TM in CPU
features, and enable a new user feature to signal to userspace that we
are in this mode.
We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we
do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace
that the kernel will abort transactions on syscall entry, which is
true regardless of the suspend mode.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Some CPUs can operate in a mode where TM (Transactional Memory) is
enabled but the suspended state of TM is disabled. In this mode
tsuspend does not enter suspended state, instead the transaction is
aborted. Similarly any other event that would lead to suspended state
instead aborts the transaction.
There is also an ABI change, in that in this mode processes are not
allowed to sigreturn with an MSR that would lead to suspended state,
Linux will instead return an error to the sigreturn syscall.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Currently the kernel relies on firmware to inform it whether or not the
CPU supports HTM and as long as the kernel was built with
CONFIG_PPC_TRANSACTIONAL_MEM=y then it will allow userspace to make
use of the facility.
There may be situations where it would be advantageous for the kernel
to not allow userspace to use HTM, currently the only way to achieve
this is to recompile the kernel with CONFIG_PPC_TRANSACTIONAL_MEM=n.
This patch adds a simple commandline option so that HTM can be
disabled at boot time.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Simplify to a bool, move to prom.c, put doco in the right place.
Always disable, regardless of initial state, to avoid user confusion.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Bring in some KVM commits we need (the TM one in particular).
|
|
Currently we use CPU_FTR_TM to decide if the CPU/kernel can support
TM (Transactional Memory), and if it's true we advertise that to
Qemu (or similar) via KVM_CAP_PPC_HTM.
PPC_FEATURE2_HTM is the user-visible feature bit, which indicates that
the CPU and kernel can support TM. Currently CPU_FTR_TM and
PPC_FEATURE2_HTM always have the same value, either true or false, so
using the former for KVM_CAP_PPC_HTM is correct.
However some Power9 CPUs can operate in a mode where TM is enabled but
TM suspended state is disabled. In this mode CPU_FTR_TM is true, but
PPC_FEATURE2_HTM is false. Instead a different PPC_FEATURE2 bit is
set, to indicate that this different mode of TM is available.
It is not safe to let guests use TM as-is, when the CPU is in this
mode. So to prevent that from happening, use PPC_FEATURE2_HTM to
determine the value of KVM_CAP_PPC_HTM.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
After we removed all the dead wood it turns out only two architectures
actually implement dma_cache_sync as a real op: mips and parisc. Add
a cache_sync method to struct dma_map_ops and implement it for the
mips defualt DMA ops, and the parisc pa11 ops.
Note that arm, arc and openrisc support DMA_ATTR_NON_CONSISTENT, but
never provided a functional dma_cache_sync implementations, which
seems somewhat odd.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
|