Commit graph

226,546 commits

Author SHA1 Message Date
Nathan Chancellor
ac04ef405d powerpc: Adjust adding stack protector flags to KBUILD_CLAGS for clang
commit bee08a9e6a upstream.

After fixing the HAVE_STACKPROTECTER checks for clang's in-progress
per-task stack protector support [1], the build fails during prepare0
because '-mstack-protector-guard-offset' has not been added to
KBUILD_CFLAGS yet but the other '-mstack-protector-guard' flags have.

  clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default
  clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default
  make[4]: *** [scripts/Makefile.build:229: scripts/mod/empty.o] Error 1
  make[4]: *** [scripts/Makefile.build:102: scripts/mod/devicetable-offsets.s] Error 1

Mirror other architectures and add all '-mstack-protector-guard' flags
to KBUILD_CFLAGS atomically during stack_protector_prepare, which
resolves the issue and allows clang's implementation to fully work with
the kernel.

Cc: stable@vger.kernel.org # 6.1+
Link: https://github.com/llvm/llvm-project/pull/110928 [1]
Reviewed-by: Keith Packard <keithp@keithp.com>
Tested-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241009-powerpc-fix-stackprotector-test-clang-v2-2-12fb86b31857@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:10 +01:00
Nathan Chancellor
fab0610d64 powerpc: Fix stack protector Kconfig test for clang
commit 46e1879dee upstream.

Clang's in-progress per-task stack protector support [1] does not work
with the current Kconfig checks because '-mstack-protector-guard-offset'
is not provided, unlike all other architecture Kconfig checks.

  $ fd Kconfig -x rg -l mstack-protector-guard-offset
  ./arch/arm/Kconfig
  ./arch/riscv/Kconfig
  ./arch/arm64/Kconfig

This produces an error from clang, which is interpreted as the flags not
being supported at all when they really are.

  $ clang --target=powerpc64-linux-gnu \
          -mstack-protector-guard=tls \
          -mstack-protector-guard-reg=r13 \
          -c -o /dev/null -x c /dev/null
  clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default

This argument will always be provided by the build system, so mirror
other architectures and use '-mstack-protector-guard-offset=0' for
testing support, which fixes the issue for clang and does not regress
support with GCC.

Even with the first problem addressed, the 32-bit test continues to fail
because Kbuild uses the powerpc64le-linux-gnu target for clang and
nothing flips the target to 32-bit, resulting in an error about an
invalid register valid:

  $ clang --target=powerpc64le-linux-gnu \
          -mstack-protector-guard=tls
          -mstack-protector-guard-reg=r2 \
          -mstack-protector-guard-offset=0 \
          -x c -c -o /dev/null /dev/null
  clang: error: invalid value 'r2' in 'mstack-protector-guard-reg=', expected one of: r13

While GCC allows arbitrary registers, the implementation of
'-mstack-protector-guard=tls' in LLVM shares the same code path as the
user space thread local storage implementation, which uses a fixed
register (2 for 32-bit and 13 for 62-bit), so the command line parsing
enforces this limitation.

Use the Kconfig macro '$(m32-flag)', which expands to '-m32' when
supported, in the stack protector support cc-option call to properly
switch the target to a 32-bit one, which matches what happens in Kbuild.
While the 64-bit macro does not strictly need it, add the equivalent
64-bit option for symmetry.

Cc: stable@vger.kernel.org # 6.1+
Link: https://github.com/llvm/llvm-project/pull/110928 [1]
Reviewed-by: Keith Packard <keithp@keithp.com>
Tested-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241009-powerpc-fix-stackprotector-test-clang-v2-1-12fb86b31857@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:10 +01:00
Heiko Carstens
20c2635782 s390/stacktrace: Use break instead of return statement
commit 588a9836a4 upstream.

arch_stack_walk_user_common() contains a return statement instead of a
break statement in case store_ip() fails while trying to store a callchain
entry of a user space process.
This may lead to a missing pagefault_enable() call.

If this happens any subsequent page fault of the process won't be resolved
by the page fault handler and this in turn will lead to the process being
killed.

Use a break instead of a return statement to fix this.

Fixes: ebd912ff99 ("s390/stacktrace: Merge perf_callchain_user() and arch_stack_walk_user()")
Cc: stable@vger.kernel.org
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:06 +01:00
Linus Walleij
0cfd6929fa ARM: 9431/1: mm: Pair atomic_set_release() with _read_acquire()
commit 93ee385254 upstream.

The code for syncing vmalloc memory PGD pointers is using
atomic_read() in pair with atomic_set_release() but the
proper pairing is atomic_read_acquire() paired with
atomic_set_release().

This is done to clearly instruct the compiler to not
reorder the memcpy() or similar calls inside the section
so that we do not observe changes to init_mm. memcpy()
calls should be identified by the compiler as having
unpredictable side effects, but let's try to be on the
safe side.

Cc: stable@vger.kernel.org
Fixes: d31e23aff0 ("ARM: mm: make vmalloc_seq handling SMP safe")
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:03 +01:00
Linus Walleij
c86d26b4b0 ARM: 9430/1: entry: Do a dummy read from VMAP shadow
commit 44e9a3bb76 upstream.

When switching task, in addition to a dummy read from the new
VMAP stack, also do a dummy read from the VMAP stack's
corresponding KASAN shadow memory to sync things up in
the new MM context.

Cc: stable@vger.kernel.org
Fixes: a1c510d0ad ("ARM: implement support for vmap'ed stacks")
Link: https://lore.kernel.org/linux-arm-kernel/a1a1d062-f3a2-4d05-9836-3b098de9db6d@foss.st.com/
Reported-by: Clement LE GOFFIC <clement.legoffic@foss.st.com>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:03 +01:00
Vasily Gorbik
473ffae303 s390/entry: Mark IRQ entries to fix stack depot warnings
commit 45c9f2b856 upstream.

The stack depot filters out everything outside of the top interrupt
context as an uninteresting or irrelevant part of the stack traces. This
helps with stack trace de-duplication, avoiding an explosion of saved
stack traces that share the same IRQ context code path but originate
from different randomly interrupted points, eventually exhausting the
stack depot.

Filtering uses in_irqentry_text() to identify functions within the
.irqentry.text and .softirqentry.text sections, which then become the
last stack trace entries being saved.

While __do_softirq() is placed into the .softirqentry.text section by
common code, populating .irqentry.text is architecture-specific.

Currently, the .irqentry.text section on s390 is empty, which prevents
stack depot filtering and de-duplication and could result in warnings
like:

Stack depot reached limit capacity
WARNING: CPU: 0 PID: 286113 at lib/stackdepot.c:252 depot_alloc_stack+0x39a/0x3c8

with PREEMPT and KASAN enabled.

Fix this by moving the IO/EXT interrupt handlers from .kprobes.text into
the .irqentry.text section and updating the kprobes blacklist to include
the .irqentry.text section.

This is done only for asynchronous interrupts and explicitly not for
program checks, which are synchronous and where the context beyond the
program check is important to preserve. Despite machine checks being
somewhat in between, they are extremely rare, and preserving context
when possible is also of value.

SVCs and Restart Interrupts are not relevant, one being always at the
boundary to user space and the other being a one-time thing.

IRQ entries filtering is also optionally used in ftrace function graph,
where the same logic applies.

Cc: stable@vger.kernel.org # 5.15+
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:03 +01:00
Linus Walleij
ad6750c17f ARM: 9429/1: ioremap: Sync PGDs for VMALLOC shadow
commit d6e6a74d4c upstream.

When sync:ing the VMALLOC area to other CPUs, make sure to also
sync the KASAN shadow memory for the VMALLOC area, so that we
don't get stale entries for the shadow memory in the top level PGD.

Since we are now copying PGDs in two instances, create a helper
function named memcpy_pgd() to do the actual copying, and
create a helper to map the addresses of VMALLOC_START and
VMALLOC_END into the corresponding shadow memory.

Co-developed-by: Melon Liu <melon1335@163.com>

Cc: stable@vger.kernel.org
Fixes: 565cbaad83 ("ARM: 9202/1: kasan: support CONFIG_KASAN_VMALLOC")
Link: https://lore.kernel.org/linux-arm-kernel/a1a1d062-f3a2-4d05-9836-3b098de9db6d@foss.st.com/
Reported-by: Clement LE GOFFIC <clement.legoffic@foss.st.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:03 +01:00
Nathan Chancellor
d63516b1e0 powerpc/vdso: Drop -mstack-protector-guard flags in 32-bit files with clang
commit d677ce5213 upstream.

Under certain conditions, the 64-bit '-mstack-protector-guard' flags may
end up in the 32-bit vDSO flags, resulting in build failures due to the
structure of clang's argument parsing of the stack protector options,
which validates the arguments of the stack protector guard flags
unconditionally in the frontend, choking on the 64-bit values when
targeting 32-bit:

  clang: error: invalid value 'r13' in 'mstack-protector-guard-reg=', expected one of: r2
  clang: error: invalid value 'r13' in 'mstack-protector-guard-reg=', expected one of: r2
  make[3]: *** [arch/powerpc/kernel/vdso/Makefile:85: arch/powerpc/kernel/vdso/vgettimeofday-32.o] Error 1
  make[3]: *** [arch/powerpc/kernel/vdso/Makefile:87: arch/powerpc/kernel/vdso/vgetrandom-32.o] Error 1

Remove these flags by adding them to the CC32FLAGSREMOVE variable, which
already handles situations similar to this. Additionally, reformat and
align a comment better for the expanding CONFIG_CC_IS_CLANG block.

Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241030-powerpc-vdso-drop-stackp-flags-clang-v1-1-d95e7376d29c@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:41:02 +01:00
Francesco Dolcini
6f655bc1f7 arm64: dts: freescale: imx8mp-verdin: Fix SD regulator startup delay
commit 6c5789c9d2 upstream.

The power switch used to power the SD card interface might have
more than 2ms turn-on time, increase the startup delay to 20ms to
prevent failures.

Fixes: a39ed23bdf ("arm64: dts: freescale: add initial support for verdin imx8m plus")
Cc: stable@vger.kernel.org
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:40:58 +01:00
Chen-Yu Tsai
3f94622dbe arm64: dts: mediatek: mt8186-corsola: Fix IT6505 reset line polarity
commit fbcc95fceb upstream.

The reset line of the IT6505 bridge chip is active low, not active high.
It was incorrectly inverted in the device tree as the implementation at
the time incorrectly inverted the polarity in its driver, due to a prior
device having an inline inverting level shifter.

Fix the polarity now while the external display pipeline is incomplete,
thereby avoiding any impact to running systems.

A matching fix for the driver should be included if this change is
backported.

Fixes: 8855d01fb8 ("arm64: dts: mediatek: Add MT8186 Krabby platform based Tentacruel / Tentacool")
Cc: stable@vger.kernel.org
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20241029100226.660263-1-wenst@chromium.org
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:40:57 +01:00
Francesco Dolcini
2bea1d0e57 arm64: dts: ti: k3-am62-verdin: Fix SD regulator startup delay
commit 2213ca5199 upstream.

The power switch used to power the SD card interface might have
more than 2ms turn-on time, increase the startup delay to 20ms to
prevent failures.

Fixes: 316b80246b ("arm64: dts: ti: add verdin am62")
Cc: stable@vger.kernel.org
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Link: https://lore.kernel.org/r/20241024130628.49650-1-francesco@dolcini.it
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:40:57 +01:00
Francesco Dolcini
5d71869f33 arm64: dts: freescale: imx8mm-verdin: Fix SD regulator startup delay
commit 0ca7699c37 upstream.

The power switch used to power the SD card interface might have
more than 2ms turn-on time, increase the startup delay to 20ms to
prevent failures.

Fixes: 6a57f224f7 ("arm64: dts: freescale: add initial support for verdin imx8m mini")
Cc: stable@vger.kernel.org
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:40:57 +01:00
Chen-Yu Tsai
e7f2429130 arm64: dts: mediatek: mt8186-corsola: Fix GPU supply coupling max-spread
commit 2f1aab0cb0 upstream.

The GPU SRAM supply is supposed to be always at least 0.1V higher than
the GPU supply. However when the DT was upstreamed, the spread was
incorrectly set to 0.01V.

Fixes: 8855d01fb8 ("arm64: dts: mediatek: Add MT8186 Krabby platform based Tentacruel / Tentacool")
Cc: stable@vger.kernel.org
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20241021140537.3049232-1-wenst@chromium.org
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:40:57 +01:00
Dragan Simic
cd70598eb0 arm64: dts: allwinner: pinephone: Add mount matrix to accelerometer
commit 2496b2aaac upstream.

The way InvenSense MPU-6050 accelerometer is mounted on the user-facing side
of the Pine64 PinePhone mainboard, which makes it rotated 90 degrees counter-
clockwise, [1] requires the accelerometer's x- and y-axis to be swapped, and
the direction of the accelerometer's y-axis to be inverted.

Rectify this by adding a mount-matrix to the accelerometer definition in the
Pine64 PinePhone dtsi file.

[1] https://files.pine64.org/doc/PinePhone/PinePhone%20mainboard%20bottom%20placement%20v1.1%2020191031.pdf

Fixes: 91f480d409 ("arm64: dts: allwinner: Add initial support for Pine64 PinePhone")
Cc: stable@vger.kernel.org
Suggested-by: Ondrej Jirman <megi@xff.cz>
Suggested-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
Reviewed-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Link: https://patch.msgid.link/129f0c754d071cca1db5d207d9d4a7bd9831dff7.1726773282.git.dsimic@manjaro.org
[wens@csie.org: Replaced Helped-by with Suggested-by]
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09 10:40:57 +01:00
Tiwei Bie
f1ed1fbad9 um: Always dump trace for specified task in show_stack
[ Upstream commit 0f659ff362 ]

Currently, show_stack() always dumps the trace of the current task.
However, it should dump the trace of the specified task if one is
provided. Otherwise, things like running "echo t > sysrq-trigger"
won't work as expected.

Fixes: 970e51fead ("um: Add support for CONFIG_STACKTRACE")
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20241106103933.1132365-1-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:03 +01:00
Tiwei Bie
f5e01fe96c um: ubd: Initialize ubd's disk pointer in ubd_add
[ Upstream commit df700802ab ]

Currently, the initialization of the disk pointer in the ubd structure
is missing. It should be initialized with the allocated gendisk pointer
in ubd_add().

Fixes: 32621ad7a7 ("ubd: remove the ubd_gendisk array")
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20241104163203.435515-2-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:03 +01:00
Tiwei Bie
a60368b192 um: Fix the return value of elf_core_copy_task_fpregs
[ Upstream commit 865e3845ee ]

This function is expected to return a boolean value, which should be
true on success and false on failure.

Fixes: d1254b12c9 ("uml: fix x86_64 core dump crash")
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20240913023302.130300-1-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:02 +01:00
Tiwei Bie
a9c95f787b um: Fix potential integer overflow during physmem setup
[ Upstream commit a98b7761f6 ]

This issue happens when the real map size is greater than LONG_MAX,
which can be easily triggered on UML/i386.

Fixes: fe205bdd13 ("um: Print minimum physical memory requirement")
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20240916045950.508910-3-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:03:02 +01:00
Borislav Petkov (AMD)
dbdec47842 x86/microcode/AMD: Flush patch buffer mapping after application
commit c809b0d0e5 upstream.

Due to specific requirements while applying microcode patches on Zen1
and 2, the patch buffer mapping needs to be flushed from the TLB after
application. Do so.

If not, unnecessary and unnatural delays happen in the boot process.

Reported-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Cc: <stable@kernel.org> # f1d84b59cb ("x86/mm: Carve out INVLPG inline asm for use by others")
Link: https://lore.kernel.org/r/ZyulbYuvrkshfsd2@antipodes
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:57 +01:00
Borislav Petkov (AMD)
12d6164199 x86/mm: Carve out INVLPG inline asm for use by others
commit f1d84b59cb upstream.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/ZyulbYuvrkshfsd2@antipodes
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:57 +01:00
Chen-Yu Tsai
b6a1ba1915 arm64: dts: mediatek: mt8186-corsola-voltorb: Merge speaker codec nodes
commit 26ea2459d1 upstream.

The Voltorb device uses a speaker codec different from the original
Corsola device. When the Voltorb device tree was first added, the new
codec was added as a separate node when it should have just replaced the
existing one.

Merge the two nodes. The only differences are the compatible string and
the GPIO line property name. This keeps the device node path for the
speaker codec the same across the MT8186 Chromebook line. Also rename
the related labels and node names from having rt1019p to speaker codec.

Cc: stable@vger.kernel.org # v6.11+
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20241018082113.1297268-1-wenst@chromium.org
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:56 +01:00
Will Deacon
e4d1f38bc0 arm64: tls: Fix context-switching of tpidrro_el0 when kpti is enabled
commit 67ab51cbdf upstream.

Commit 18011eac28 ("arm64: tls: Avoid unconditional zeroing of
tpidrro_el0 for native tasks") tried to optimise the context switching
of tpidrro_el0 by eliding the clearing of the register when switching
to a native task with kpti enabled, on the erroneous assumption that
the kpti trampoline entry code would already have taken care of the
write.

Although the kpti trampoline does zero the register on entry from a
native task, the check in tls_thread_switch() is on the *next* task and
so we can end up leaving a stale, non-zero value in the register if the
previous task was 32-bit.

Drop the broken optimisation and zero tpidrro_el0 unconditionally when
switching to a native 64-bit task.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Fixes: 18011eac28 ("arm64: tls: Avoid unconditional zeroing of tpidrro_el0 for native tasks")
Signed-off-by: Will Deacon <will@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20241114095332.23391-1-will@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:55 +01:00
Huacai Chen
701e329006 sh: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK
commit 3c891f7c6a upstream.

When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS are selected,
cpu_max_bits_warn() generates a runtime warning similar as below when
showing /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit)
instead of NR_CPUS to iterate CPUs.

[    3.052463] ------------[ cut here ]------------
[    3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0
[    3.070072] Modules linked in: efivarfs autofs4
[    3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052
[    3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000
[    3.109127]         9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430
[    3.118774]         90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff
[    3.128412]         0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890
[    3.138056]         0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa
[    3.147711]         ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000
[    3.157364]         900000000101c998 0000000000000004 9000000000ef7430 0000000000000000
[    3.167012]         0000000000000009 000000000000006c 0000000000000000 0000000000000000
[    3.176641]         9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286
[    3.186260]         00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c
[    3.195868]         ...
[    3.199917] Call Trace:
[    3.203941] [<90000000002086d8>] show_stack+0x38/0x14c
[    3.210666] [<9000000000cf846c>] dump_stack_lvl+0x60/0x88
[    3.217625] [<900000000023d268>] __warn+0xd0/0x100
[    3.223958] [<9000000000cf3c90>] warn_slowpath_fmt+0x7c/0xcc
[    3.231150] [<9000000000210220>] show_cpuinfo+0x5e8/0x5f0
[    3.238080] [<90000000004f578c>] seq_read_iter+0x354/0x4b4
[    3.245098] [<90000000004c2e90>] new_sync_read+0x17c/0x1c4
[    3.252114] [<90000000004c5174>] vfs_read+0x138/0x1d0
[    3.258694] [<90000000004c55f8>] ksys_read+0x70/0x100
[    3.265265] [<9000000000cfde9c>] do_syscall+0x7c/0x94
[    3.271820] [<9000000000202fe4>] handle_syscall+0xc4/0x160
[    3.281824] ---[ end trace 8b484262b4b8c24c ]---

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:55 +01:00
Tiwei Bie
12f52e373d um: vector: Do not use drvdata in release
commit 51b39d7419 upstream.

The drvdata is not available in release. Let's just use container_of()
to get the vector_device instance. Otherwise, removing a vector device
will result in a crash:

RIP: 0033:vector_device_release+0xf/0x50
RSP: 00000000e187bc40  EFLAGS: 00010202
RAX: 0000000060028f61 RBX: 00000000600f1baf RCX: 00000000620074e0
RDX: 000000006220b9c0 RSI: 0000000060551c80 RDI: 0000000000000000
RBP: 00000000e187bc50 R08: 00000000603ad594 R09: 00000000e187bb70
R10: 000000000000135a R11: 00000000603ad422 R12: 00000000623ae028
R13: 000000006287a200 R14: 0000000062006d30 R15: 00000000623700b6
Kernel panic - not syncing: Segfault with no mm
CPU: 0 UID: 0 PID: 16 Comm: kworker/0:1 Not tainted 6.12.0-rc6-g59b723cd2adb #1
Workqueue: events mc_work_proc
Stack:
 60028f61 623ae028 e187bc80 60276fcd
 6220b9c0 603f5820 623ae028 00000000
 e187bcb0 603a2bcd 623ae000 62370010
Call Trace:
 [<60028f61>] ? vector_device_release+0x0/0x50
 [<60276fcd>] device_release+0x70/0xba
 [<603a2bcd>] kobject_put+0xba/0xe7
 [<60277265>] put_device+0x19/0x1c
 [<60281266>] platform_device_put+0x26/0x29
 [<60281e5f>] platform_device_unregister+0x2c/0x2e
 [<60029422>] vector_remove+0x52/0x58
 [<60031316>] ? mconsole_reply+0x0/0x50
 [<600310c8>] mconsole_remove+0x160/0x1cc
 [<603b19f4>] ? strlen+0x0/0x15
 [<60066611>] ? __dequeue_entity+0x1a9/0x206
 [<600666a7>] ? set_next_entity+0x39/0x63
 [<6006666e>] ? set_next_entity+0x0/0x63
 [<60038fa6>] ? um_set_signals+0x0/0x43
 [<6003070c>] mc_work_proc+0x77/0x91
 [<60057664>] process_scheduled_works+0x1b3/0x2dd
 [<60055f32>] ? assign_work+0x0/0x58
 [<60057f0a>] worker_thread+0x1e9/0x293
 [<6005406f>] ? set_pf_worker+0x0/0x64
 [<6005d65d>] ? arch_local_irq_save+0x0/0x2d
 [<6005d748>] ? kthread_exit+0x0/0x3a
 [<60057d21>] ? worker_thread+0x0/0x293
 [<6005dbf1>] kthread+0x126/0x12b
 [<600219c5>] new_thread_handler+0x85/0xb6

Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20241104163203.435515-5-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:54 +01:00
Tiwei Bie
f04cd022ee um: net: Do not use drvdata in release
commit d1db692a9b upstream.

The drvdata is not available in release. Let's just use container_of()
to get the uml_net instance. Otherwise, removing a network device will
result in a crash:

RIP: 0033:net_device_release+0x10/0x6f
RSP: 00000000e20c7c40  EFLAGS: 00010206
RAX: 000000006002e4e7 RBX: 00000000600f1baf RCX: 00000000624074e0
RDX: 0000000062778000 RSI: 0000000060551c80 RDI: 00000000627af028
RBP: 00000000e20c7c50 R08: 00000000603ad594 R09: 00000000e20c7b70
R10: 000000000000135a R11: 00000000603ad422 R12: 0000000000000000
R13: 0000000062c7af00 R14: 0000000062406d60 R15: 00000000627700b6
Kernel panic - not syncing: Segfault with no mm
CPU: 0 UID: 0 PID: 29 Comm: kworker/0:2 Not tainted 6.12.0-rc6-g59b723cd2adb #1
Workqueue: events mc_work_proc
Stack:
 627af028 62c7af00 e20c7c80 60276fcd
 62778000 603f5820 627af028 00000000
 e20c7cb0 603a2bcd 627af000 62770010
Call Trace:
 [<60276fcd>] device_release+0x70/0xba
 [<603a2bcd>] kobject_put+0xba/0xe7
 [<60277265>] put_device+0x19/0x1c
 [<60281266>] platform_device_put+0x26/0x29
 [<60281e5f>] platform_device_unregister+0x2c/0x2e
 [<6002ec9c>] net_remove+0x63/0x69
 [<60031316>] ? mconsole_reply+0x0/0x50
 [<600310c8>] mconsole_remove+0x160/0x1cc
 [<60087d40>] ? __remove_hrtimer+0x38/0x74
 [<60087ff8>] ? hrtimer_try_to_cancel+0x8c/0x98
 [<6006b3cf>] ? dl_server_stop+0x3f/0x48
 [<6006b390>] ? dl_server_stop+0x0/0x48
 [<600672e8>] ? dequeue_entities+0x327/0x390
 [<60038fa6>] ? um_set_signals+0x0/0x43
 [<6003070c>] mc_work_proc+0x77/0x91
 [<60057664>] process_scheduled_works+0x1b3/0x2dd
 [<60055f32>] ? assign_work+0x0/0x58
 [<60057f0a>] worker_thread+0x1e9/0x293
 [<6005406f>] ? set_pf_worker+0x0/0x64
 [<6005d65d>] ? arch_local_irq_save+0x0/0x2d
 [<6005d748>] ? kthread_exit+0x0/0x3a
 [<60057d21>] ? worker_thread+0x0/0x293
 [<6005dbf1>] kthread+0x126/0x12b
 [<600219c5>] new_thread_handler+0x85/0xb6

Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20241104163203.435515-4-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:53 +01:00
Tiwei Bie
16cf851168 um: ubd: Do not use drvdata in release
commit 5bee35e538 upstream.

The drvdata is not available in release. Let's just use container_of()
to get the ubd instance. Otherwise, removing a ubd device will result
in a crash:

RIP: 0033:blk_mq_free_tag_set+0x1f/0xba
RSP: 00000000e2083bf0  EFLAGS: 00010246
RAX: 000000006021463a RBX: 0000000000000348 RCX: 0000000062604d00
RDX: 0000000004208060 RSI: 00000000605241a0 RDI: 0000000000000348
RBP: 00000000e2083c10 R08: 0000000062414010 R09: 00000000601603f7
R10: 000000000000133a R11: 000000006038c4bd R12: 0000000000000000
R13: 0000000060213a5c R14: 0000000062405d20 R15: 00000000604f7aa0
Kernel panic - not syncing: Segfault with no mm
CPU: 0 PID: 17 Comm: kworker/0:1 Not tainted 6.8.0-rc3-00107-gba3f67c11638 #1
Workqueue: events mc_work_proc
Stack:
 00000000 604f7ef0 62c5d000 62405d20
 e2083c30 6002c776 6002c755 600e47ff
 e2083c60 6025ffe3 04208060 603d36e0
Call Trace:
 [<6002c776>] ubd_device_release+0x21/0x55
 [<6002c755>] ? ubd_device_release+0x0/0x55
 [<600e47ff>] ? kfree+0x0/0x100
 [<6025ffe3>] device_release+0x70/0xba
 [<60381d6a>] kobject_put+0xb5/0xe2
 [<6026027b>] put_device+0x19/0x1c
 [<6026a036>] platform_device_put+0x26/0x29
 [<6026ac5a>] platform_device_unregister+0x2c/0x2e
 [<6002c52e>] ubd_remove+0xb8/0xd6
 [<6002bb74>] ? mconsole_reply+0x0/0x50
 [<6002b926>] mconsole_remove+0x160/0x1cc
 [<6002bbbc>] ? mconsole_reply+0x48/0x50
 [<6003379c>] ? um_set_signals+0x3b/0x43
 [<60061c55>] ? update_min_vruntime+0x14/0x70
 [<6006251f>] ? dequeue_task_fair+0x164/0x235
 [<600620aa>] ? update_cfs_group+0x0/0x40
 [<603a0e77>] ? __schedule+0x0/0x3ed
 [<60033761>] ? um_set_signals+0x0/0x43
 [<6002af6a>] mc_work_proc+0x77/0x91
 [<600520b4>] process_scheduled_works+0x1af/0x2c3
 [<6004ede3>] ? assign_work+0x0/0x58
 [<600527a1>] worker_thread+0x2f7/0x37a
 [<6004ee3b>] ? set_pf_worker+0x0/0x64
 [<6005765d>] ? arch_local_irq_save+0x0/0x2d
 [<60058e07>] ? kthread_exit+0x0/0x3a
 [<600524aa>] ? worker_thread+0x0/0x37a
 [<60058f9f>] kthread+0x130/0x135
 [<6002068e>] new_thread_handler+0x85/0xb6

Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20241104163203.435515-3-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:53 +01:00
Sebastian Andrzej Siewior
ccfee14f08 x86/CPU/AMD: Terminate the erratum_1386_microcode array
commit ff6cdc407f upstream.

The erratum_1386_microcode array requires an empty entry at the end.
Otherwise x86_match_cpu_with_stepping() will continue iterate the array after
it ended.

Add an empty entry to erratum_1386_microcode to its end.

Fixes: 29ba89f189 ("x86/CPU/AMD: Improve the erratum 1386 workaround")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20241126134722.480975-1-bigeasy@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:53 +01:00
Jesse Taube
c4ae2baea5 RISC-V: Check scalar unaligned access on all CPUs
commit 8d20a739f1 upstream.

Originally, the check_unaligned_access_emulated_all_cpus function
only checked the boot hart. This fixes the function to check all
harts.

Fixes: 71c54b3d16 ("riscv: report misaligned accesses emulation to hwprobe")
Signed-off-by: Jesse Taube <jesse@rivosinc.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20241017-jesse_unaligned_vector-v10-1-5b33500160f8@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:52 +01:00
Jesse Taube
2bb3830152 RISC-V: Scalar unaligned access emulated on hotplug CPUs
commit 9c528b5f79 upstream.

The check_unaligned_access_emulated() function should have been called
during CPU hotplug to ensure that if all CPUs had emulated unaligned
accesses, the new CPU also does.

This patch adds the call to check_unaligned_access_emulated() in
the hotplug path.

Fixes: 55e0bf49a0 ("RISC-V: Probe misaligned access speed in parallel")
Signed-off-by: Jesse Taube <jesse@rivosinc.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20241017-jesse_unaligned_vector-v10-2-5b33500160f8@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:52 +01:00
Josh Poimboeuf
3017be7b84 parisc/ftrace: Fix function graph tracing disablement
commit a5f05a138a upstream.

Due to an apparent copy-paste bug, the parisc implementation of
ftrace_disable_ftrace_graph_caller() doesn't actually do anything.
It enables the (already-enabled) static key rather than disabling it.

The result is that after function graph tracing has been "disabled", any
subsequent (non-graph) function tracing will inadvertently also enable
the slow fgraph return address hijacking.

Fixes: 98f2926171 ("parisc/ftrace: use static key to enable/disable function graph tracer")
Cc: stable@vger.kernel.org # 5.16+
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:52 +01:00
Andreas Kemnade
522614145a ARM: dts: omap36xx: declare 1GHz OPP as turbo again
commit 96a64e9730 upstream.

Operating stable without reduced chip life at 1Ghz needs several
technologies working: The technologies involve
- SmartReflex
- DVFS

As this cannot directly specified in the OPP table as dependecies in the
devicetree yet, use the turbo flag again to mark this OPP as something
special to have some kind of opt-in.

So revert commit
5f1bf7ae84 ("ARM: dts: omap36xx: Remove turbo mode for 1GHz variants")

Practical reasoning:
At least the GTA04A5 (DM3730) has become unstable with that OPP enabled.
Furthermore nothing enforces the availability of said technologies,
even in the kernel configuration, so allow users to rather opt-in.

Cc: Stable@vger.kernel.org
Fixes: 5f1bf7ae84 ("ARM: dts: omap36xx: Remove turbo mode for 1GHz variants")
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Link: https://lore.kernel.org/r/20241018214727.275162-1-andreas@kemnade.info
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:49 +01:00
Huacai Chen
7b3a7918f1 LoongArch: Explicitly specify code model in Makefile
commit e67e0eb6a9 upstream.

LoongArch's toolchain may change the default code model from normal to
medium. This is unnecessary for kernel, and generates some relocations
which cannot be handled by the module loader. So explicitly specify the
code model to normal in Makefile (for Rust 'normal' is 'small').

Cc: stable@vger.kernel.org
Tested-by: Haiyong Sun <sunhaiyong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:45 +01:00
Kunkun Jiang
1059f1e5f5 KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a device
commit e9649129d3 upstream.

vgic_its_save_device_tables will traverse its->device_list to
save DTE for each device. vgic_its_restore_device_tables will
traverse each entry of device table and check if it is valid.
Restore if valid.

But when MAPD unmaps a device, it does not invalidate the
corresponding DTE. In the scenario of continuous saves
and restores, there may be a situation where a device's DTE
is not saved but is restored. This is unreasonable and may
cause restore to fail. This patch clears the corresponding
DTE when MAPD unmaps a device.

Cc: stable@vger.kernel.org
Fixes: 57a9a11715 ("KVM: arm64: vgic-its: Device table save/restore")
Co-developed-by: Shusen Li <lishusen2@huawei.com>
Signed-off-by: Shusen Li <lishusen2@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
[Jing: Update with entry write helper]
Signed-off-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20241107214137.428439-5-jingzhangos@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:45 +01:00
Jing Zhang
46018a04c5 KVM: arm64: vgic-its: Add a data length check in vgic_its_save_*
commit 7fe28d7e68 upstream.

In all the vgic_its_save_*() functinos, they do not check whether
the data length is 8 bytes before calling vgic_write_guest_lock.
This patch adds the check. To prevent the kernel from being blown up
when the fault occurs, KVM_BUG_ON() is used. And the other BUG_ON()s
are replaced together.

Cc: stable@vger.kernel.org
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
[Jing: Update with the new entry read/write helpers]
Signed-off-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20241107214137.428439-4-jingzhangos@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Raghavendra Rao Ananta
fe425d5239 KVM: arm64: Get rid of userspace_irqchip_in_use
commit 38d7aacca0 upstream.

Improper use of userspace_irqchip_in_use led to syzbot hitting the
following WARN_ON() in kvm_timer_update_irq():

WARNING: CPU: 0 PID: 3281 at arch/arm64/kvm/arch_timer.c:459
kvm_timer_update_irq+0x21c/0x394
Call trace:
  kvm_timer_update_irq+0x21c/0x394 arch/arm64/kvm/arch_timer.c:459
  kvm_timer_vcpu_reset+0x158/0x684 arch/arm64/kvm/arch_timer.c:968
  kvm_reset_vcpu+0x3b4/0x560 arch/arm64/kvm/reset.c:264
  kvm_vcpu_set_target arch/arm64/kvm/arm.c:1553 [inline]
  kvm_arch_vcpu_ioctl_vcpu_init arch/arm64/kvm/arm.c:1573 [inline]
  kvm_arch_vcpu_ioctl+0x112c/0x1b3c arch/arm64/kvm/arm.c:1695
  kvm_vcpu_ioctl+0x4ec/0xf74 virt/kvm/kvm_main.c:4658
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:907 [inline]
  __se_sys_ioctl fs/ioctl.c:893 [inline]
  __arm64_sys_ioctl+0x108/0x184 fs/ioctl.c:893
  __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
  invoke_syscall+0x78/0x1b8 arch/arm64/kernel/syscall.c:49
  el0_svc_common+0xe8/0x1b0 arch/arm64/kernel/syscall.c:132
  do_el0_svc+0x40/0x50 arch/arm64/kernel/syscall.c:151
  el0_svc+0x54/0x14c arch/arm64/kernel/entry-common.c:712
  el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
  el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

The following sequence led to the scenario:
 - Userspace creates a VM and a vCPU.
 - The vCPU is initialized with KVM_ARM_VCPU_PMU_V3 during
   KVM_ARM_VCPU_INIT.
 - Without any other setup, such as vGIC or vPMU, userspace issues
   KVM_RUN on the vCPU. Since the vPMU is requested, but not setup,
   kvm_arm_pmu_v3_enable() fails in kvm_arch_vcpu_run_pid_change().
   As a result, KVM_RUN returns after enabling the timer, but before
   incrementing 'userspace_irqchip_in_use':
   kvm_arch_vcpu_run_pid_change()
       ret = kvm_arm_pmu_v3_enable()
           if (!vcpu->arch.pmu.created)
               return -EINVAL;
       if (ret)
           return ret;
       [...]
       if (!irqchip_in_kernel(kvm))
           static_branch_inc(&userspace_irqchip_in_use);
 - Userspace ignores the error and issues KVM_ARM_VCPU_INIT again.
   Since the timer is already enabled, control moves through the
   following flow, ultimately hitting the WARN_ON():
   kvm_timer_vcpu_reset()
       if (timer->enabled)
          kvm_timer_update_irq()
              if (!userspace_irqchip())
                  ret = kvm_vgic_inject_irq()
                      ret = vgic_lazy_init()
                          if (unlikely(!vgic_initialized(kvm)))
                              if (kvm->arch.vgic.vgic_model !=
                                  KVM_DEV_TYPE_ARM_VGIC_V2)
                                      return -EBUSY;
                  WARN_ON(ret);

Theoretically, since userspace_irqchip_in_use's functionality can be
simply replaced by '!irqchip_in_kernel()', get rid of the static key
to avoid the mismanagement, which also helps with the syzbot issue.

Cc: <stable@vger.kernel.org>
Reported-by: syzbot <syzkaller@googlegroups.com>
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Kunkun Jiang
eabd7ef140 KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITE
commit 7602ffd1d5 upstream.

When DISCARD frees an ITE, it does not invalidate the
corresponding ITE. In the scenario of continuous saves and
restores, there may be a situation where an ITE is not saved
but is restored. This is unreasonable and may cause restore
to fail. This patch clears the corresponding ITE when DISCARD
frees an ITE.

Cc: stable@vger.kernel.org
Fixes: eff484e029 ("KVM: arm64: vgic-its: ITT save and restore")
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
[Jing: Update with entry write helper]
Signed-off-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20241107214137.428439-6-jingzhangos@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Oliver Upton
d0571c3add KVM: arm64: Don't retire aborted MMIO instruction
commit e735a5da64 upstream.

Returning an abort to the guest for an unsupported MMIO access is a
documented feature of the KVM UAPI. Nevertheless, it's clear that this
plumbing has seen limited testing, since userspace can trivially cause a
WARN in the MMIO return:

  WARNING: CPU: 0 PID: 30558 at arch/arm64/include/asm/kvm_emulate.h:536 kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536
  Call trace:
   kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536
   kvm_arch_vcpu_ioctl_run+0x98/0x15b4 arch/arm64/kvm/arm.c:1133
   kvm_vcpu_ioctl+0x75c/0xa78 virt/kvm/kvm_main.c:4487
   __do_sys_ioctl fs/ioctl.c:51 [inline]
   __se_sys_ioctl fs/ioctl.c:893 [inline]
   __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893
   __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
   invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
   el0_svc_common+0x1e0/0x23c arch/arm64/kernel/syscall.c:132
   do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
   el0_svc+0x38/0x68 arch/arm64/kernel/entry-common.c:712
   el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730
   el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

The splat is complaining that KVM is advancing PC while an exception is
pending, i.e. that KVM is retiring the MMIO instruction despite a
pending synchronous external abort. Womp womp.

Fix the glaring UAPI bug by skipping over all the MMIO emulation in
case there is a pending synchronous exception. Note that while userspace
is capable of pending an asynchronous exception (SError, IRQ, or FIQ),
it is still safe to retire the MMIO instruction in this case as (1) they
are by definition asynchronous, and (2) KVM relies on hardware support
for pending/delivering these exceptions instead of the software state
machine for advancing PC.

Cc: stable@vger.kernel.org
Fixes: da345174ce ("KVM: arm/arm64: Allow user injection of external data aborts")
Reported-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025203106.3529261-2-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Sean Christopherson
f3c6fa7ce9 Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()"
commit 85434c3c73 upstream.

Revert back to clearing VM_{ENTRY,EXIT}_LOAD_IA32_PERF_GLOBAL_CTRL in KVM's
golden VMCS config, as applying the workaround during vCPU creation is
pointless and broken.  KVM *unconditionally* clears the controls in the
values returned by vmx_vmentry_ctrl() and vmx_vmexit_ctrl(), as KVM loads
PERF_GLOBAL_CTRL if and only if its necessary to do so.  E.g. if KVM wants
to run the guest with the same PERF_GLOBAL_CTRL as the host, then there's
no need to re-load the MSR on entry and exit.

Even worse, the buggy commit failed to apply the erratum where it's
actually needed, add_atomic_switch_msr().  As a result, KVM completely
ignores the erratum for all intents and purposes, i.e. uses the flawed
VMCS controls to load PERF_GLOBAL_CTRL.

To top things off, the patch was intended to be dropped, as the premise
of an L1 VMM being able to pivot on FMS is flawed, and KVM can (and now
does) fully emulate the controls in software.  Simply revert the commit,
as all upstream supported kernels that have the buggy commit should also
have commit f4c93d1a0e ("KVM: nVMX: Always emulate PERF_GLOBAL_CTRL
VM-Entry/VM-Exit controls"), i.e. the (likely theoretical) live migration
concern is a complete non-issue.

Opportunistically drop the manual "kvm: " scope from the warning about
the erratum, as KVM now uses pr_fmt() to provide the correct scope (v6.1
kernels and earlier don't, but the erratum only applies to CPUs that are
15+ years old; it's not worth a separate patch).

This reverts commit 9d78d6fb18.

Link: https://lore.kernel.org/all/YtnZmCutdd5tpUmz@google.com
Fixes: 9d78d6fb18 ("KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()")
Cc: stable@vger.kernel.org
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-ID: <20241119011433.1797921-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Raghavendra Rao Ananta
8b6916f4cf KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow status
commit 54bbee190d upstream.

DDI0487K.a D13.3.1 describes the PMU overflow condition, which evaluates
to true if any counter's global enable (PMCR_EL0.E), overflow flag
(PMOVSSET_EL0[n]), and interrupt enable (PMINTENSET_EL1[n]) are all 1.
Of note, this does not require a counter to be enabled
(i.e. PMCNTENSET_EL0[n] = 1) to generate an overflow.

Align kvm_pmu_overflow_status() with the reality of the architecture
and stop using PMCNTENSET_EL0 as part of the overflow condition. The
bug was discovered while running an SBSA PMU test [*], which only sets
PMCR.E, PMOVSSET<0>, PMINTENSET<0>, and expects an overflow interrupt.

Cc: stable@vger.kernel.org
Fixes: 76d883c4e6 ("arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR register")
Link: https://github.com/ARM-software/sbsa-acs/blob/master/test_pool/pmu/operating_system/test_pmu001.c
Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
[ oliver: massaged changelog ]
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241120005230.2335682-2-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Marc Zyngier
f594a5683a KVM: arm64: vgic-v3: Sanitise guest writes to GICR_INVLPIR
commit d561491ba9 upstream.

Make sure we filter out non-LPI invalidation when handling writes
to GICR_INVLPIR.

Fixes: 4645d11f4a ("KVM: arm64: vgic-v3: Implement MMIO-based LPI invalidation")
Reported-by: Alexander Potapenko <glider@google.com>
Tested-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20241117165757.247686-2-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:44 +01:00
Gautam Menghani
58d6473042 powerpc/pseries: Fix KVM guest detection for disabling hardlockup detector
commit 44e5d21e6d upstream.

As per the kernel documentation[1], hardlockup detector should
be disabled in KVM guests as it may give false positives. On
PPC, hardlockup detector is enabled inside KVM guests because
disable_hardlockup_detector() is marked as early_initcall and it
relies on kvm_guest static key (is_kvm_guest()) which is initialized
later during boot by check_kvm_guest(), which is a core_initcall.
check_kvm_guest() is also called in pSeries_smp_probe(), which is called
before initcalls, but it is skipped if KVM guest does not have doorbell
support or if the guest is launched with SMT=1.

Call check_kvm_guest() in disable_hardlockup_detector() so that
is_kvm_guest() check goes through fine and hardlockup detector can be
disabled inside the KVM guest.

[1]: Documentation/admin-guide/sysctl/kernel.rst

Fixes: 633c8e9800 ("powerpc/pseries: Enable hardlockup watchdog for PowerVM partitions")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241108094839.33084-1-gautam@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Sean Christopherson
952741d54d KVM: x86: Break CONFIG_KVM_X86's direct dependency on KVM_INTEL || KVM_AMD
commit 9ee62c33c0 upstream.

Rework CONFIG_KVM_X86's dependency to only check if KVM_INTEL or KVM_AMD
is selected, i.e. not 'n'.  Having KVM_X86 depend directly on the vendor
modules results in KVM_X86 being set to 'm' if at least one of KVM_INTEL
or KVM_AMD is enabled, but neither is 'y', regardless of the value of KVM
itself.

The documentation for def_tristate doesn't explicitly state that this is
the intended behavior, but it does clearly state that the "if" section is
parsed as a dependency, i.e. the behavior is consistent with how tristate
dependencies are handled in general.

  Optionally dependencies for this default value can be added with "if".

Fixes: ea4290d77b ("KVM: x86: leave kvm.ko out of the build if no vendor module is requested")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20241118172002.1633824-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Arnd Bergmann
b44026c099 KVM: x86: add back X86_LOCAL_APIC dependency
commit 1331343af6 upstream.

Enabling KVM now causes a build failure on x86-32 if X86_LOCAL_APIC
is disabled:

arch/x86/kvm/svm/svm.c: In function 'svm_emergency_disable_virtualization_cpu':
arch/x86/kvm/svm/svm.c:597:9: error: 'kvm_rebooting' undeclared (first use in this function); did you mean 'kvm_irq_routing'?
  597 |         kvm_rebooting = true;
      |         ^~~~~~~~~~~~~
      |         kvm_irq_routing
arch/x86/kvm/svm/svm.c:597:9: note: each undeclared identifier is reported only once for each function it appears in
make[6]: *** [scripts/Makefile.build:221: arch/x86/kvm/svm/svm.o] Error 1
In file included from include/linux/rculist.h:11,
                 from include/linux/hashtable.h:14,
                 from arch/x86/kvm/svm/avic.c:18:
arch/x86/kvm/svm/avic.c: In function 'avic_pi_update_irte':
arch/x86/kvm/svm/avic.c:909:38: error: 'struct kvm' has no member named 'irq_routing'
  909 |         irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
      |                                      ^~
include/linux/rcupdate.h:538:17: note: in definition of macro '__rcu_dereference_check'
  538 |         typeof(*p) *local = (typeof(*p) *__force)READ_ONCE(p); \

Move the dependency to the same place as before.

Fixes: ea4290d77b ("KVM: x86: leave kvm.ko out of the build if no vendor module is requested")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202410060426.e9Xsnkvi-lkp@intel.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sean Christopherson <seanjc@google.com>
[sean: add Cc to stable, tweak shortlog scope]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20241118172002.1633824-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Sean Christopherson
cb02ac1579 KVM: x86/mmu: Skip the "try unsync" path iff the old SPTE was a leaf SPTE
commit 2867eb782c upstream.

Apply make_spte()'s optimization to skip trying to unsync shadow pages if
and only if the old SPTE was a leaf SPTE, as non-leaf SPTEs in direct MMUs
are always writable, i.e. could trigger a false positive and incorrectly
lead to KVM creating a SPTE without write-protecting or marking shadow
pages unsync.

This bug only affects the TDP MMU, as the shadow MMU only overwrites a
shadow-present SPTE when synchronizing SPTEs (and only 4KiB SPTEs can be
unsync).  Specifically, mmu_set_spte() drops any non-leaf SPTEs *before*
calling make_spte(), whereas the TDP MMU can do a direct replacement of a
page table with the leaf SPTE.

Opportunistically update the comment to explain why skipping the unsync
stuff is safe, as opposed to simply saying "it's someone else's problem".

Cc: stable@vger.kernel.org
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20241010182427.1434605-5-seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Paolo Bonzini
91248a2e41 KVM: x86: switch hugepage recovery thread to vhost_task
commit d96c77bd4e upstream.

kvm_vm_create_worker_thread() is meant to be used for kthreads that
can consume significant amounts of CPU time on behalf of a VM or in
response to how the VM behaves (for example how it accesses its memory).
Therefore it wants to charge the CPU time consumed by that work to
the VM's container.

However, because of these threads, cgroups which have kvm instances
inside never complete freezing.  This can be trivially reproduced:

  root@test ~# mkdir /sys/fs/cgroup/test
  root@test ~# echo $$ > /sys/fs/cgroup/test/cgroup.procs
  root@test ~# qemu-system-x86_64 -nographic -enable-kvm

and in another terminal:

  root@test ~# echo 1 > /sys/fs/cgroup/test/cgroup.freeze
  root@test ~# cat /sys/fs/cgroup/test/cgroup.events
  populated 1
  frozen 0

The cgroup freezing happens in the signal delivery path but
kvm_nx_huge_page_recovery_worker, while joining non-root cgroups, never
calls into the signal delivery path and thus never gets frozen. Because
the cgroup freezer determines whether a given cgroup is frozen by
comparing the number of frozen threads to the total number of threads
in the cgroup, the cgroup never becomes frozen and users waiting for
the state transition may hang indefinitely.

Since the worker kthread is tied to a user process, it's better if
it behaves similarly to user tasks as much as possible, including
being able to send SIGSTOP and SIGCONT.  In fact, vhost_task is all
that kvm_vm_create_worker_thread() wanted to be and more: not only it
inherits the userspace process's cgroups, it has other niceties like
being parented properly in the process tree.  Use it instead of the
homegrown alternative.

Incidentally, the new code is also better behaved when you flip recovery
back and forth to disabled and back to enabled.  If your recovery period
is 1 minute, it will run the next recovery after 1 minute independent
of how many times you flipped the parameter.

(Commit message based on emails from Tejun).

Reported-by: Tejun Heo <tj@kernel.org>
Reported-by: Luca Boccassi <bluca@debian.org>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Luca Boccassi <bluca@debian.org>
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Eric Biggers
d6933f2ea2 crypto: x86/aegis128 - access 32-bit arguments as 32-bit
commit 3b2f2d22fb upstream.

Fix the AEGIS assembly code to access 'unsigned int' arguments as 32-bit
values instead of 64-bit, since the upper bits of the corresponding
64-bit registers are not guaranteed to be zero.

Note: there haven't been any reports of this bug actually causing
incorrect behavior.  Neither gcc nor clang guarantee zero-extension to
64 bits, but zero-extension is likely to happen in practice because most
instructions that operate on 32-bit registers zero-extend to 64 bits.

Fixes: 1d373d4e8e ("crypto: x86 - Add optimized AEGIS implementations")
Cc: stable@vger.kernel.org
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Adrian Hunter
bc9b40fae6 perf/x86/intel/pt: Fix buffer full but size is 0 case
commit 5b590160d2 upstream.

If the trace data buffer becomes full, a truncated flag [T] is reported
in PERF_RECORD_AUX.  In some cases, the size reported is 0, even though
data must have been added to make the buffer full.

That happens when the buffer fills up from empty to full before the
Intel PT driver has updated the buffer position.  Then the driver
calculates the new buffer position before calculating the data size.
If the old and new positions are the same, the data size is reported
as 0, even though it is really the whole buffer size.

Fix by detecting when the buffer position is wrapped, and adjust the
data size calculation accordingly.

Example

  Use a very small buffer size (8K) and observe the size of truncated [T]
  data. Before the fix, it is possible to see records of 0 size.

  Before:

    $ perf record -m,8K -e intel_pt// uname
    Linux
    [ perf record: Woken up 2 times to write data ]
    [ perf record: Captured and wrote 0.105 MB perf.data ]
    $ perf script -D --no-itrace | grep AUX | grep -F '[T]'
    Warning:
    AUX data lost 2 times out of 3!

    5 19462712368111 0x19710 [0x40]: PERF_RECORD_AUX offset: 0 size: 0 flags: 0x1 [T]
    5 19462712700046 0x19ba8 [0x40]: PERF_RECORD_AUX offset: 0x170 size: 0xe90 flags: 0x1 [T]

 After:

    $ perf record -m,8K -e intel_pt// uname
    Linux
    [ perf record: Woken up 3 times to write data ]
    [ perf record: Captured and wrote 0.040 MB perf.data ]
    $ perf script -D --no-itrace | grep AUX | grep -F '[T]'
    Warning:
    AUX data lost 2 times out of 3!

    1 113720802995 0x4948 [0x40]: PERF_RECORD_AUX offset: 0 size: 0x2000 flags: 0x1 [T]
    1 113720979812 0x6b10 [0x40]: PERF_RECORD_AUX offset: 0x2000 size: 0x2000 flags: 0x1 [T]

Fixes: 52ca9ced3f ("perf/x86/intel/pt: Add Intel PT PMU driver")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20241022155920.17511-2-adrian.hunter@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05 14:02:43 +01:00
Niklas Schnelle
371bd90559 s390/pci: Fix potential double remove of hotplug slot
[ Upstream commit c4a585e952 ]

In commit 6ee600bfbe ("s390/pci: remove hotplug slot when releasing the
device") the zpci_exit_slot() was moved from zpci_device_reserved() to
zpci_release_device() with the intention of keeping the hotplug slot
around until the device is actually removed.

Now zpci_release_device() is only called once all references are
dropped. Since the zPCI subsystem only drops its reference once the
device is in the reserved state it follows that zpci_release_device()
must only deal with devices in the reserved state. Despite that it
contains code to tear down from both configured and standby state. For
the standby case this already includes the removal of the hotplug slot
so would cause a double removal if a device was ever removed in
either configured or standby state.

Instead of causing a potential double removal in a case that should
never happen explicitly WARN_ON() if a device in non-reserved state is
released and get rid of the dead code cases.

Fixes: 6ee600bfbe ("s390/pci: remove hotplug slot when releasing the device")
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com>
Tested-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:40 +01:00
Tiezhu Yang
d5d83242a1 LoongArch: BPF: Sign-extend return values
[ Upstream commit 73c359d1d3 ]

(1) Description of Problem:

When testing BPF JIT with the latest compiler toolchains on LoongArch,
there exist some strange failed test cases, dmesg shows something like
this:

  # dmesg -t | grep FAIL | head -1
  ... ret -3 != -3 (0xfffffffd != 0xfffffffd)FAIL ...

(2) Steps to Reproduce:

  # echo 1 > /proc/sys/net/core/bpf_jit_enable
  # modprobe test_bpf

(3) Additional Info:

There are no failed test cases compiled with the lower version of GCC
such as 13.3.0, while the problems only appear with higher version of
GCC such as 14.2.0.

This is because the problems were hidden by the lower version of GCC due
to redundant sign extension instructions generated by compiler, but with
optimization of higher version of GCC, the sign extension instructions
have been removed.

(4) Root Cause Analysis:

The LoongArch architecture does not expose sub-registers, and hold all
32-bit values in a sign-extended format. While BPF, on the other hand,
exposes sub-registers, and use zero-extension (similar to arm64/x86).

This has led to some subtle bugs, where a BPF JITted program has not
sign-extended the a0 register (return value in LoongArch land), passed
the return value up the kernel, for example:

  | int from_bpf(void);
  |
  | long foo(void)
  | {
  |    return from_bpf();
  | }

Here, a0 would be 0xffffffff instead of the expected 0xffffffffffffffff.

Internally, the LoongArch JIT uses a5 as a dedicated register for BPF
return values. That is to say, the LoongArch BPF uses a5 for BPF return
values, which are zero-extended, whereas the LoongArch ABI uses a0 which
is sign-extended.

(5) Final Solution:

Keep a5 zero-extended, but explicitly sign-extend a0 (which is used
outside BPF land). Because libbpf currently defines the return value
of an ebpf program as a 32-bit unsigned integer, just use addi.w to
extend bit 31 into bits 63 through 32 of a5 to a0. This is similar to
commit 2f1b0d3d73 ("riscv, bpf: Sign-extend return values").

Fixes: 5dc615520c ("LoongArch: Add BPF JIT support")
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:29 +01:00
Tiezhu Yang
cd5364ed17 LoongArch: Fix build failure with GCC 15 (-std=gnu23)
[ Upstream commit 947d5d036c ]

Whenever I try to build the kernel with upcoming GCC 15 which defaults
to -std=gnu23 I get a build failure:

  CC      arch/loongarch/vdso/vgetcpu.o
In file included from ./include/uapi/linux/posix_types.h:5,
                 from ./include/uapi/linux/types.h:14,
                 from ./include/linux/types.h:6,
                 from ./include/linux/kasan-checks.h:5,
                 from ./include/asm-generic/rwonce.h:26,
                 from ./arch/loongarch/include/generated/asm/rwonce.h:1,
                 from ./include/linux/compiler.h:317,
                 from ./include/asm-generic/bug.h:5,
                 from ./arch/loongarch/include/asm/bug.h:60,
                 from ./include/linux/bug.h:5,
                 from ./include/linux/mmdebug.h:5,
                 from ./include/linux/mm.h:6,
                 from ./arch/loongarch/include/asm/vdso.h:10,
                 from arch/loongarch/vdso/vgetcpu.c:6:
./include/linux/stddef.h:11:9: error: expected identifier before 'false'
   11 |         false   = 0,
      |         ^~~~~
./include/linux/types.h:35:33: error: two or more data types in declaration specifiers
   35 | typedef _Bool                   bool;
      |                                 ^~~~
./include/linux/types.h:35:1: warning: useless type name in empty declaration
   35 | typedef _Bool                   bool;
      | ^~~~~~~

The kernel builds explicitly with -std=gnu11 in top Makefile, but
arch/loongarch/vdso does not use KBUILD_CFLAGS from the rest of the
kernel, just add -std=gnu11 flag to arch/loongarch/vdso/Makefile.

By the way, commit e8c07082a8 ("Kbuild: move to -std=gnu11") did a
similar change for arch/arm64/kernel/vdso32/Makefile.

Fixes: c6b99bed6b ("LoongArch: Add VDSO and VSYSCALL support")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05 14:02:29 +01:00