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Linux kernel
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Pull Kbuild fixes from Masahiro Yamada:
- Deduplicate Kconfig entries for CONFIG_CXL_PMU
- Fix unselectable choice entry in MIPS Kconfig, and forbid this
structure
- Remove unused include/asm-generic/export.h
- Fix a NULL pointer dereference bug in modpost
- Enable -Woverride-init warning consistently with W=1
- Drop KCSAN flags from *.mod.c files
* tag 'kbuild-fixes-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: Fix typo HEIGTH to HEIGHT
Documentation/llvm: Note s390 LLVM=1 support with LLVM 18.1.0 and newer
kbuild: Disable KCSAN for autogenerated *.mod.c intermediaries
kbuild: make -Woverride-init warnings more consistent
modpost: do not make find_tosym() return NULL
export.h: remove include/asm-generic/export.h
kconfig: do not reparent the menu inside a choice block
MIPS: move unselectable FIT_IMAGE_FDT_EPM5 out of the "System type" choice
cxl: remove CONFIG_CXL_PMU entry in drivers/cxl/Kconfig
Pull EDAC fixes from Borislav Petkov:
- Fix more issues in the AMD FMPM driver
* tag 'edac_urgent_for_v6.9_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
RAS: Avoid build errors when CONFIG_DEBUG_FS=n
RAS/AMD/FMPM: Safely handle saved records of various sizes
RAS/AMD/FMPM: Avoid NULL ptr deref in get_saved_records()
Fixed a typo in some variables where height was misspelled as heigth.
Signed-off-by: Isak Ellmer <isak01@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull irq fixes from Borislav Petkov:
- Fix an unused function warning on irqchip/irq-armada-370-xp
- Fix the IRQ sharing with pinctrl-amd and ACPI OSL
* tag 'irq_urgent_for_v6.9_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/armada-370-xp: Suppress unused-function warning
genirq: Introduce IRQF_COND_ONESHOT and use it in pinctrl-amd
A new helper was introduced for RAS modules to be able to get the RAS
subsystem debugfs root directory. The helper is defined in debugfs.c
which is only built when CONFIG_DEBUG_FS=y.
However, it's possible that the modules would include debugfs support
for optional functionality. One current example is the fmpm module. In
this case, a build error will occur when CONFIG_RAS_FMPM is selected and
CONFIG_DEBUG_FS=n.
Add an inline helper function stub for the CONFIG_DEBUG_FS=n case as the
fmpm module can function without the debugfs functionality too.
Fixes: 9d2b6fa09d15 ("RAS: Export helper to get ras_debugfs_dir")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218640
Reported-by: anthony s. knowles <akira.2020@protonmail.com>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: anthony s. knowles <akira.2020@protonmail.com>
Link: https://lore.kernel.org/r/20240325183755.776-1-bp@alien8.de
As of the first s390 pull request during the 6.9 merge window,
commit 691632f0e869 ("Merge tag 's390-6.9-1' of
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux"), s390 can be
built with LLVM=1 when using LLVM 18.1.0, which is the first version
that has SystemZ support implemented in ld.lld and llvm-objcopy.
Update the supported architectures table in the Kbuild LLVM
documentation to note this explicitly to make it more discoverable by
users and other developers. Additionally, this brings s390 in line with
the rest of the architectures in the table, which all support LLVM=1.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull x86 perf fixes from Borislav Petkov:
- Define the correct set of default hw events on AMD Zen4
- Use the correct stalled cycles PMCs on AMD Zen2 and newer
- Fix detection of the LBR freeze feature on AMD
* tag 'perf_urgent_for_v6.9_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/core: Define a proper ref-cycles event for Zen 4 and later
perf/x86/amd/core: Update and fix stalled-cycles-* events for Zen 2 and later
perf/x86/amd/lbr: Use freeze based on availability
x86/cpufeatures: Add new word for scattered features
armada_370_xp_msi_reenable_percpu() is only defined when CONFIG_PCI_MSI is
enabled, and only called when SMP is enabled.
Without CONFIG_SMP, there are no callers, which results in a build time
warning instead:
drivers/irqchip/irq-armada-370-xp.c:319:13: error: 'armada_370_xp_msi_reenable_percpu' defined but not used [-Werror=unused-function]
319 | static void armada_370_xp_msi_reenable_percpu(void) {}
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Mark the function as __maybe_unused to avoid adding more complexity
to the #ifdefs.
Fixes: 8ca61cde32c1 ("irqchip/armada-370-xp: Enable MSI affinity configuration")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240322125838.901649-1-arnd@kernel.org
Currently, the size of the locally cached FRU record structures is
based on the module parameter "max_nr_entries".
This creates issues when restoring records if a user changes the
parameter.
If the number of entries is reduced, then old, larger records will not
be restored. The opportunity to take action on the saved data is missed.
Also, new records will be created and written to storage, even as the old
records remain in storage, resulting in wasted space.
If the number of entries is increased, then the length of the old,
smaller records will not be adjusted. This causes a checksum failure
which leads to the old record being cleared from storage. Again this
results in another missed opportunity for action on the saved data.
Allocate the temporary record with the maximum possible size based on
the current maximum number of supported entries (255). This allows the
ERST read operation to succeed if max_nr_entries has been increased.
Warn the user if a saved record exceeds the expected size and fail to
load the module. This allows the user to adjust the module parameter
without losing data or the opportunity to restore larger records.
Increase the size of a saved record up to the current max_rec_len. The
checksum will be recalculated, and the updated record will be written to
storage.
Fixes: 6f15e617cc99 ("RAS: Introduce a FRU memory poison manager")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Muralidhara M K <muralidhara.mk@amd.com>
Link: https://lore.kernel.org/r/20240319113322.280096-3-yazen.ghannam@amd.com
When KCSAN and CONSTRUCTORS are enabled, one can trigger the
"Unpatched return thunk in use. This should not happen!"
catch-all warning.
Usually, when objtool runs on the .o objects, it does generate a section
.return_sites which contains all offsets in the objects to the return
thunks of the functions present there. Those return thunks then get
patched at runtime by the alternatives.
KCSAN and CONSTRUCTORS add this to the object file's .text.startup
section:
-------------------
Disassembly of section .text.startup:
...
0000000000000010 <_sub_I_00099_0>:
10: f3 0f 1e fa endbr64
14: e8 00 00 00 00 call 19 <_sub_I_00099_0+0x9>
15: R_X86_64_PLT32 __tsan_init-0x4
19: e9 00 00 00 00 jmp 1e <__UNIQUE_ID___addressable_cryptd_alloc_aead349+0x6>
1a: R_X86_64_PLT32 __x86_return_thunk-0x4
-------------------
which, if it is built as a module goes through the intermediary stage of
creating a <module>.mod.c file which, when translated, receives a second
constructor:
-------------------
Disassembly of section .text.startup:
0000000000000010 <_sub_I_00099_0>:
10: f3 0f 1e fa endbr64
14: e8 00 00 00 00 call 19 <_sub_I_00099_0+0x9>
15: R_X86_64_PLT32 __tsan_init-0x4
19: e9 00 00 00 00 jmp 1e <_sub_I_00099_0+0xe>
1a: R_X86_64_PLT32 __x86_return_thunk-0x4
...
0000000000000030 <_sub_I_00099_0>:
30: f3 0f 1e fa endbr64
34: e8 00 00 00 00 call 39 <_sub_I_00099_0+0x9>
35: R_X86_64_PLT32 __tsan_init-0x4
39: e9 00 00 00 00 jmp 3e <__ksymtab_cryptd_alloc_ahash+0x2>
3a: R_X86_64_PLT32 __x86_return_thunk-0x4
-------------------
in the .ko file.
Objtool has run already so that second constructor's return thunk cannot
be added to the .return_sites section and thus the return thunk remains
unpatched and the warning rightfully fires.
Drop KCSAN flags from the mod.c generation stage as those constructors
do not contain data races one would be interested about.
Debugged together with David Kaplan <David.Kaplan@amd.com> and Nikolay
Borisov <nik.borisov@suse.com>.
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Closes: https://lore.kernel.org/r/0851a207-7143-417e-be31-8bf2b3afb57d@molgen.mpg.de
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de> # Dell XPS 13
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Reviewed-by: Marco Elver <elver@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull timers update from Borislav Petkov:
- Volunteer in Anna-Maria and Frederic as timers co-maintainers so that
tglx can relax more :-P
* tag 'timers_urgent_for_v6.9_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
MAINTAINERS: Add co-maintainers for time[rs]
Add the "ref-cycles" event for AMD processors based on Zen 4 and later
microarchitectures. The backing event is based on PMCx120 which counts
cycles not in halt state in P0 frequency (same as MPERF).
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/089155f19f7c7e65aeb1caa727a882e2ca9b8b04.1711352180.git.sandipan.das@amd.com
There is a problem when a driver requests a shared interrupt line to run a
threaded handler on it without IRQF_ONESHOT set if that flag has been set
already for the IRQ in question by somebody else. Namely, the request
fails which usually leads to a probe failure even though the driver might
have worked just fine with IRQF_ONESHOT, but it does not want to use it by
default. Currently, the only way to handle this is to try to request the
IRQ without IRQF_ONESHOT, but with IRQF_PROBE_SHARED set and if this fails,
try again with IRQF_ONESHOT set. However, this is a bit cumbersome and not
very clean.
When commit 7a36b901a6eb ("ACPI: OSL: Use a threaded interrupt handler for
SCI") switched the ACPI subsystem over to using a threaded interrupt
handler for the SCI, it had to use IRQF_ONESHOT for it because that's
required due to the way the SCI handler works (it needs to walk all of the
enabled GPEs before the interrupt line can be unmasked). The SCI interrupt
line is not shared with other users very often due to the SCI handling
overhead, but on sone systems it is shared and when the other user of it
attempts to install a threaded handler, a flags mismatch related to
IRQF_ONESHOT may occur.
As it turned out, that happened to the pinctrl-amd driver and so commit
4451e8e8415e ("pinctrl: amd: Add IRQF_ONESHOT to the interrupt request")
attempted to address the issue by adding IRQF_ONESHOT to the interrupt
flags in that driver, but this is now causing an IRQF_ONESHOT-related
mismatch to occur on another system which cannot boot as a result of it.
Clearly, pinctrl-amd can work with IRQF_ONESHOT if need be, but it should
not set that flag by default, so it needs a way to indicate that to the
interrupt subsystem.
To that end, introdcuce a new interrupt flag, IRQF_COND_ONESHOT, which will
only have effect when the IRQ line is shared and IRQF_ONESHOT has been set
for it already, in which case it will be promoted to the latter.
This is sufficient for drivers sharing the interrupt line with the SCI as
it is requested by the ACPI subsystem before any drivers are probed, so
they will always see IRQF_ONESHOT set for the interrupt in question.
Fixes: 4451e8e8415e ("pinctrl: amd: Add IRQF_ONESHOT to the interrupt request")
Reported-by: Francisco Ayala Le Brun <francisco@videowindow.eu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: 6.8+ <stable@vger.kernel.org> # 6.8+
Closes: https://lore.kernel.org/lkml/CAN-StX1HqWqi+YW=t+V52-38Mfp5fAz7YHx4aH-CQjgyNiKx3g@mail.gmail.com/
Link: https://lore.kernel.org/r/12417336.O9o76ZdvQC@kreacher
An old, invalid record should be cleared and skipped.
Currently, the record is cleared in ERST, but it is not skipped. This
leads to a NULL pointer dereference when attempting to copy the old
record to the new record.
Continue the loop after clearing an old, invalid record to skip it.
Fixes: 6f15e617cc99 ("RAS: Introduce a FRU memory poison manager")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Muralidhara M K <muralidhara.mk@amd.com>
Link: https://lore.kernel.org/r/20240319113322.280096-2-yazen.ghannam@amd.com
The -Woverride-init warn about code that may be intentional or not,
but the inintentional ones tend to be real bugs, so there is a bit of
disagreement on whether this warning option should be enabled by default
and we have multiple settings in scripts/Makefile.extrawarn as well as
individual subsystems.
Older versions of clang only supported -Wno-initializer-overrides with
the same meaning as gcc's -Woverride-init, though all supported versions
now work with both. Because of this difference, an earlier cleanup of
mine accidentally turned the clang warning off for W=1 builds and only
left it on for W=2, while it's still enabled for gcc with W=1.
There is also one driver that only turns the warning off for newer
versions of gcc but not other compilers, and some but not all the
Makefiles still use a cc-disable-warning conditional that is no
longer needed with supported compilers here.
Address all of the above by removing the special cases for clang
and always turning the warning off unconditionally where it got
in the way, using the syntax that is supported by both compilers.
Fixes: 2cd3271b7a31 ("kbuild: avoid duplicate warning options")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Andrew Jeffery <andrew@codeconstruct.com.au>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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