The flogr() inline assembly has no side effects and generates the same
output if the input does not change. Therefore remove the volatile
qualifier to allow the compiler to optimize the inline assembly away,
if possible.
Also remove the superfluous '\n' which makes the inline assembly appear
larger than it is according to compiler heuristics (number of lines).
Furthermore change the return type of flogr() to unsigned long and add the
const attribute to the function.
This reduces the kernel image size by 994 bytes (defconfig, gcc 15.2.0).
Suggested-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Use __assume() to tell compilers that the output operand of the __flogr()
inline assembly contains a value in the range of 0..64. This allows to
optimize the logical AND operation away.
This reduces the kernel image size by 2804 bytes (defconfig, gcc 15.2.0).
Suggested-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Make the statement attribute "assume" with a new __assume macro available.
The assume attribute is used to indicate that a certain condition is
assumed to be true. Compilers may or may not use this indication to
generate optimized code. If this condition is violated at runtime, the
behavior is undefined.
Note that the clang documentation states that optimizers may react
differently to this attribute, and this may even have a negative
performance impact. Therefore this attribute should be used with care.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
With the recent ffs() and ffs64() optimization a logical AND operation was
removed, which allowed the compiler to tell the return value range of both
functions. This may lead to compile warnings as reported by the kernel test
robot:
drivers/infiniband/hw/mlx5/mr.c: In function 'mlx5r_cache_create_ent_locked':
>> drivers/infiniband/hw/mlx5/mr.c:840:31: warning: 'sprintf' may write a terminating nul past the end of the destination [-Wformat-overflow=]
840 | sprintf(ent->name, "%d", order);
| ^
In function 'mlx5_mkey_cache_debugfs_add_ent',
inlined from 'mlx5r_cache_create_ent_locked' at drivers/infiniband/hw/mlx5/mr.c:930:3:
drivers/infiniband/hw/mlx5/mr.c:840:9: note: 'sprintf' output between 2 and 5 bytes into a destination of size 4
840 | sprintf(ent->name, "%d", order);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Add the AND operation again to address the warning.
From a correctness point of view the AND operation is not necessary,
however there is no other way to tell the compiler that the returned
value of the flogr inline assembly is in the range of 0..64.
This increases the kernel image size by 566 bytes (defconfig, gcc 15.2.0).
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202508211859.UoYsJbLN-lkp@intel.com/
Fixes: de88e74889 ("s390/bitops: Slightly optimize ffs() and fls64()")
Suggested-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Add a test which verifies that NT_ARM_SVE and NT_ARM_SSVE reads and writes
are rejected as expected when the relevant architecture feature is not
supported.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
We do not currently have a test that asserts that we reject attempts to set
a vector length smaller than SVE_VL_MIN or larger than SVE_VL_MAX, add one
since that is our current behaviour.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Function copy_from_user() and copy_to_user() may sleep because of page
fault, and they cannot be called in spin_lock hold context. Here move
function calling of copy_from_user() and copy_to_user() out of spinlock
context in function kvm_pch_pic_regs_access().
Otherwise there will be possible warning such as:
BUG: sleeping function called from invalid context at include/linux/uaccess.h:192
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 6292, name: qemu-system-loo
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
irq event stamp: 0
hardirqs last enabled at (0): [<0000000000000000>] 0x0
hardirqs last disabled at (0): [<9000000004c4a554>] copy_process+0x90c/0x1d40
softirqs last enabled at (0): [<9000000004c4a554>] copy_process+0x90c/0x1d40
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 41 UID: 0 PID: 6292 Comm: qemu-system-loo Tainted: G W 6.17.0-rc3+ #31 PREEMPT(full)
Tainted: [W]=WARN
Stack : 0000000000000076 0000000000000000 9000000004c28264 9000100092ff4000
9000100092ff7b80 9000100092ff7b88 0000000000000000 9000100092ff7cc8
9000100092ff7cc0 9000100092ff7cc0 9000100092ff7a00 0000000000000001
0000000000000001 9000100092ff7b88 947d2f9216a5e8b9 900010008773d880
00000000ffff8b9f fffffffffffffffe 0000000000000ba1 fffffffffffffffe
000000000000003e 900000000825a15b 000010007ad38000 9000100092ff7ec0
0000000000000000 0000000000000000 9000000006f3ac60 9000000007252000
0000000000000000 00007ff746ff2230 0000000000000053 9000200088a021b0
0000555556c9d190 0000000000000000 9000000004c2827c 000055556cfb5f40
00000000000000b0 0000000000000007 0000000000000007 0000000000071c1d
Call Trace:
[<9000000004c2827c>] show_stack+0x5c/0x180
[<9000000004c20fac>] dump_stack_lvl+0x94/0xe4
[<9000000004c99c7c>] __might_resched+0x26c/0x290
[<9000000004f68968>] __might_fault+0x20/0x88
[<ffff800002311de0>] kvm_pch_pic_regs_access.isra.0+0x88/0x380 [kvm]
[<ffff8000022f8514>] kvm_device_ioctl+0x194/0x290 [kvm]
[<900000000506b0d8>] sys_ioctl+0x388/0x1010
[<90000000063ed210>] do_syscall+0xb0/0x2d8
[<9000000004c25ef8>] handle_syscall+0xb8/0x158
Cc: stable@vger.kernel.org
Fixes: d206d95148 ("LoongArch: KVM: Add PCHPIC user mode read and write functions")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
With PTW disabled system, bit _PAGE_DIRTY is a HW bit for page writing.
However with PTW enabled system, bit _PAGE_WRITE is also a "HW bit" for
page writing, because hardware synchronizes _PAGE_WRITE to _PAGE_DIRTY
automatically. Previously, _PAGE_WRITE is treated as a SW bit to record
the page writeable attribute for the fast page fault handling in the
secondary MMU, however with PTW enabled machine, this bit is used by HW
already (so setting it will silence the TLB modify exception).
Here define KVM_PAGE_WRITEABLE with the SW bit _PAGE_MODIFIED, so that
it can work on both PTW disabled and enabled machines. And for HW write
bits, both _PAGE_DIRTY and _PAGE_WRITE are set or clear together.
Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add a NULL-pointer check after the kcalloc() call in init_vdso(). If
allocation fails, return -ENOMEM to prevent a possible dereference of
vdso_info.code_mapping.pages when it is NULL.
Cc: stable@vger.kernel.org
Fixes: 2ed119aef6 ("LoongArch: Set correct size for vDSO code mapping")
Signed-off-by: Guangshuo Li <202321181@mail.sdu.edu.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When testing the kernel live patching with "modprobe livepatch-sample",
there is a timeout over 15 seconds from "starting patching transition"
to "patching complete". The dmesg command shows "unreliable stack" for
user tasks in debug mode, here is one of the messages:
livepatch: klp_try_switch_task: bash:1193 has an unreliable stack
The "unreliable stack" is because it can not unwind from do_syscall()
to its previous frame handle_syscall(). It should use fp to find the
original stack top due to secondary stack in do_syscall(), but fp is
not used for some other functions, then fp can not be restored by the
next frame of do_syscall(), so it is necessary to save fp if task is
not current, in order to get the stack top of do_syscall().
Here are the call chains:
klp_enable_patch()
klp_try_complete_transition()
klp_try_switch_task()
klp_check_and_switch_task()
klp_check_stack()
stack_trace_save_tsk_reliable()
arch_stack_walk_reliable()
When executing "rmmod livepatch-sample", there exists a similar issue.
With this patch, it takes a short time for patching and unpatching.
Before:
# modprobe livepatch-sample
# dmesg -T | tail -3
[Sat Sep 6 11:00:20 2025] livepatch: 'livepatch_sample': starting patching transition
[Sat Sep 6 11:00:35 2025] livepatch: signaling remaining tasks
[Sat Sep 6 11:00:36 2025] livepatch: 'livepatch_sample': patching complete
# echo 0 > /sys/kernel/livepatch/livepatch_sample/enabled
# rmmod livepatch_sample
rmmod: ERROR: Module livepatch_sample is in use
# rmmod livepatch_sample
# dmesg -T | tail -3
[Sat Sep 6 11:06:05 2025] livepatch: 'livepatch_sample': starting unpatching transition
[Sat Sep 6 11:06:20 2025] livepatch: signaling remaining tasks
[Sat Sep 6 11:06:21 2025] livepatch: 'livepatch_sample': unpatching complete
After:
# modprobe livepatch-sample
# dmesg -T | tail -2
[Tue Sep 16 16:19:30 2025] livepatch: 'livepatch_sample': starting patching transition
[Tue Sep 16 16:19:31 2025] livepatch: 'livepatch_sample': patching complete
# echo 0 > /sys/kernel/livepatch/livepatch_sample/enabled
# rmmod livepatch_sample
# dmesg -T | tail -2
[Tue Sep 16 16:19:36 2025] livepatch: 'livepatch_sample': starting unpatching transition
[Tue Sep 16 16:19:37 2025] livepatch: 'livepatch_sample': unpatching complete
Cc: stable@vger.kernel.org # v6.9+
Fixes: 199cc14cb4 ("LoongArch: Add kernel livepatching support")
Reported-by: Xi Zhang <zhangxi@kylinos.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
As Documentation/filesystems/sysfs.rst suggested, show() should only use
sysfs_emit() or sysfs_emit_at() when formatting the value to be returned
to user space.
No functional change intended.
Cc: stable@vger.kernel.org
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
ARCH_STRICT_ALIGN is used for hardware without UAL, now it only control
the -mstrict-align flag. However, ACPI structures are packed by default
so will cause unaligned accesses.
To avoid this, define ACPI_MISALIGNMENT_NOT_SUPPORTED in asm/acenv.h to
align ACPI structures if ARCH_STRICT_ALIGN enabled.
Cc: stable@vger.kernel.org
Reported-by: Binbin Zhou <zhoubinbin@loongson.cn>
Suggested-by: Xi Ruoyao <xry111@xry111.site>
Suggested-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Loongson-3A6000 and 3C6000 CPUs also support unaligned memory access, so
the current description is out of date to some extent.
Actually, all of Loongson-3 series processors based on LoongArch support
unaligned memory access, this hardware capability is indicated by the bit
20 (UAL) of CPUCFG1 register, update the help info to reflect the reality.
Cc: stable@vger.kernel.org
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When compiling with LLVM and CONFIG_RUST is set, there exist objtool
warnings in rust/core.o and rust/kernel.o, like this:
rust/core.o: warning: objtool:
_RNvXs1_NtNtCs5QSdWC790r4_4core5ascii10ascii_charNtB5_9AsciiCharNtNtB9_3fmt5Debug3fmt+0x54:
sibling call from callable instruction with modified stack frame
For this special case, the related object file shows that there is no
generated relocation section '.rela.discard.tablejump_annotate' for the
table jump instruction jirl, thus objtool can not know that what is the
actual destination address.
If rustc has the option "-Cllvm-args=--loongarch-annotate-tablejump",
pass the option to enable jump tables for objtool, otherwise it should
pass "-Zno-jump-tables" to keep compatibility with older rustc.
How to test:
$ rustup component add rust-src
$ make LLVM=1 rustavailable
$ make ARCH=loongarch LLVM=1 clean defconfig
$ scripts/config -d MODVERSIONS \
-e RUST -e SAMPLES -e SAMPLES_RUST \
-e SAMPLE_RUST_CONFIGFS -e SAMPLE_RUST_MINIMAL \
-e SAMPLE_RUST_MISC_DEVICE -e SAMPLE_RUST_PRINT \
-e SAMPLE_RUST_DMA -e SAMPLE_RUST_DRIVER_PCI \
-e SAMPLE_RUST_DRIVER_PLATFORM -e SAMPLE_RUST_DRIVER_FAUX \
-e SAMPLE_RUST_DRIVER_AUXILIARY -e SAMPLE_RUST_HOSTPROGS
$ make ARCH=loongarch LLVM=1 olddefconfig all
Cc: stable@vger.kernel.org
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://lore.kernel.org/rust-for-linux/CANiq72mNeCuPkCDrG2db3w=AX+O-zYrfprisDPmRac_qh65Dmg@mail.gmail.com/
Suggested-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LTO is not only used for Clang, but maybe also used for Rust, make LTO
case out of CONFIG_CC_HAS_ANNOTATE_TABLEJUMP in Makefile.
This is preparation for later patch, no function changes.
Cc: stable@vger.kernel.org
Suggested-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When compiling with LLVM and CONFIG_RUST is set, there exists the
following objtool warning:
rust/compiler_builtins.o: warning: objtool: __rust__unordsf2(): unexpected end of section .text.unlikely.
objdump shows that the end of section .text.unlikely is an atomic
instruction:
amswap.w $zero, $ra, $zero
According to the LoongArch Reference Manual, if the amswap.w atomic
memory access instruction has the same register number as rd and rj,
the execution will trigger an Instruction Non-defined Exception, so
mark the above instruction as INSN_BUG type to fix the warning.
Cc: stable@vger.kernel.org
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
If the break immediate code is 0, it should mark the type as
INSN_TRAP. If the break immediate code is 1, it should mark the
type as INSN_BUG.
While at it, format the code style and add the code comment for nop.
Cc: stable@vger.kernel.org
Suggested-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Inspired by recent changes to compression level parsing in
6db1df415d ("btrfs: accept and ignore compression level for lzo")
it turns out that we do not do any extra validation for compression
level input string, thus allowing things like "compress=lzo:invalid" to
be accepted without warnings.
Although we accept levels that are beyond the supported algorithm
ranges, accepting completely invalid level specification is not correct.
Fix the too loose checks for compression level, by doing proper error
handling of kstrtoint(), so that we will reject not only too large
values (beyond int range) but also completely wrong levels like
"lzo:invalid".
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Michael Chan says:
====================
bnxt_en: Updates for net-next
This series includes some code clean-ups and optimizations. New features
include 2 new backing store memory types to collect FW logs for core
dumps, dynamic SRIOV resource allocations for RoCE, and ethtool tunable
for PFC watchdog.
v2: Drop patch #4. The patch makes the code different from the original
bnxt_hwrm_func_backing_store_cfg_v2() that allows instance_bmap to have
bits that are not contiguous. It is safer to keep the original code.
v1: https://lore.kernel.org/netdev/20250915030505.1803478-1-michael.chan@broadcom.com/
====================
Link: https://patch.msgid.link/20250917040839.1924698-1-michael.chan@broadcom.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Improve the logic that determines the last_type in this function.
The different context memory types are configured in a loop. The
last_type signals the last context memory type to be configured
which requires the ALL_DONE flag to be set for the FW.
The existing logic makes some assumptions that TIM is the last_type
when RDMA is enabled or FTQM is the last_type when only L2 is
enabled. Improve it to just search for the last_type so that we
don't need to make these assumptions that won't necessary be true
for future devices.
Reviewed-by: Shruti Parab <shruti.parab@broadcom.com>
Reviewed-by: Hongguang Gao <hongguang.gao@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20250917040839.1924698-5-michael.chan@broadcom.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
If the table has only linear targets and there is just one underlying
device, we can optimize REQ_PREFLUSH with data - we don't have to split
it to two bios - a flush and a write. We can pass it to the linear target
directly.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Normally we wait for the socket to buffer up the whole record
before we service it. If the socket has a tiny buffer, however,
we read out the data sooner, to prevent connection stalls.
Make sure that we abort the connection when we find out late
that the record is actually invalid. Retrying the parsing is
fine in itself but since we copy some more data each time
before we parse we can overflow the allocated skb space.
Constructing a scenario in which we're under pressure without
enough data in the socket to parse the length upfront is quite
hard. syzbot figured out a way to do this by serving us the header
in small OOB sends, and then filling in the recvbuf with a large
normal send.
Make sure that tls_rx_msg_size() aborts strp, if we reach
an invalid record there's really no way to recover.
Reported-by: Lee Jones <lee@kernel.org>
Fixes: 84c61fe1a7 ("tls: rx: do not use the standard strparser")
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250917002814.1743558-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Introduce decrypt FT, the RX error FT, and the default rules.
The PSP (PSP) RX decrypt flow table is pointed by the TTC
(Traffic Type Classifier) UDP steering rules.
The decrypt flow table has two flow groups. The first flow group
keeps the decrypt steering rule programmed always when PSP packet is
recognized using the dedicated udp destination port number 1000, if
packet is decrypted then a PSP marker is set in metadata_regB[30].
The second flow group has a default rule to forward all non-offloaded
PSP packet to the TTC UDP default RSS TIR.
The RX error flow table is the destination of the decrypt steering rules in
the PSP RX decrypt flow table. It has two fixed rule one with single copy
action that copies psp_syndrome to metadata_regB[23:29]. The PSP marker
and syndrome is used to filter out non-psp packet and to return the PSP
crypto offload status in Rx flow. The marker is used to identify such
packet in driver so the driver could set SKB PSP metadata. The destination
of RX error flow table is the TTC UDP default RSS TIR. The second rule will
drop packets that failed to be decrypted (like in case illegal SPI or
expired SPI is used).
Signed-off-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250917000954.859376-16-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Dan Carpenter
Heiko Carstens
Mark Brown
Bibo Mao
Tao Cui
Guangshuo Li
Tiezhu Yang
Huacai Chen
Qu Wenruo
Paolo Abeni
Michael Chan
Kalesh AP
Anantha Prabhu
Kashyap Desai
Shruti Parab
Mikulas Patocka
Jakub Kicinski
Kuninori Morimoto
Bartosz Golaszewski
Raed Salem