The arch_calc_vm_prot_bits() macro uses VM_PKEY_BIT0 etc. which are
not part of the UAPI, so the macro is completely useless for userspace.
It is also hidden behind the CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
config switch which we shouldn't expose to userspace. Thus let's move
this macro into a new internal header instead.
Fixes: 8f62c88322 ("x86/mm/pkeys: Add arch-specific VMA protection bits")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lore.kernel.org/r/20230906162658.142511-1-thuth@redhat.com
With ":text =0xcccc", ld.lld fills unused text area with 0xcccc0000.
Example objdump -D output:
ffffffff82b04203: 00 00 add %al,(%rax)
ffffffff82b04205: cc int3
ffffffff82b04206: cc int3
ffffffff82b04207: 00 00 add %al,(%rax)
ffffffff82b04209: cc int3
ffffffff82b0420a: cc int3
Replace it with ":text =0xcccccccc", so we get the following instead:
ffffffff82b04203: cc int3
ffffffff82b04204: cc int3
ffffffff82b04205: cc int3
ffffffff82b04206: cc int3
ffffffff82b04207: cc int3
ffffffff82b04208: cc int3
gcc/ld doesn't seem to have the same issue. The generated code stays the
same for gcc/ld.
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Fixes: 7705dc8557 ("x86/vmlinux: Use INT3 instead of NOP for linker fill bytes")
Link: https://lore.kernel.org/r/20230906175215.2236033-1-song@kernel.org
System runs at minimum performance, once powercap RAPL package domain
enabled flag is changed from 1 to 0 to 1.
Setting RAPL package domain enabled flag to 0, results in setting of
power limit 4 (PL4) MSR 0x601 to 0. This implies disabling PL4 limit.
The PL4 limit controls the peak power. So setting 0, results in some
undesirable performance, which depends on hardware implementation.
Even worse, when the enabled flag is set to 1 again. This will set PL4
MSR value to 0x01, which means reduce peak power to 0.125W. This will
force system to run at the lowest possible performance on every PL4
supported system.
Setting enabled flag should only affect the "enable" bit, not other
bits. Here it is changing power limit.
This is caused by a change which assumes that there is an enable bit in
the PL4 MSR like other power limits. Although PL4 enable/disable bit is
present with TPMI RAPL interface, it is not present with the MSR
interface.
There is a rapl_primitive_info defined for non existent PL4 enable bit
and then it is used with the commit 9050a9cd5e ("powercap: intel_rapl:
Cleanup Power Limits support") to enable PL4. This is wrong, hence remove
this rapl primitive for PL4. Also in the function
rapl_detect_powerlimit(), PL_ENABLE is used to check for the presence of
power limits. Replace PL_ENABLE with PL_LIMIT, as PL_LIMIT must be
present. Without this change, PL4 controls will not be available in the
sysfs once rapl primitive for PL4 is removed.
Fixes: 9050a9cd5e ("powercap: intel_rapl: Cleanup Power Limits support")
Suggested-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: Sumeet Pawnikar <sumeet.r.pawnikar@intel.com>
Cc: 6.5+ <stable@vger.kernel.org> # 6.5+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
fscrypt support to CephFS! The list of things which don't work with
encryption should be fairly short, mostly around the edges: fallocate
(not supported well in CephFS to begin with), copy_file_range (requires
re-encryption), non-default striping patterns.
This was a multi-year effort principally by Jeff Layton with assistance
from Xiubo Li, Luís Henriques and others, including several dependant
changes in the MDS, netfs helper library and fscrypt framework itself.
-----BEGIN PGP SIGNATURE-----
iQFHBAABCAAxFiEEydHwtzie9C7TfviiSn/eOAIR84sFAmT4pl4THGlkcnlvbW92
QGdtYWlsLmNvbQAKCRBKf944AhHzi5kzB/4sMgzZyUa3T1vA/G2pPvEkyy1qDxsW
y+o4dDMWA9twcrBVpNuGd54wbXpmO/LAekHEdorjayH+f0zf10MsnP1ePz9WB3NG
jr7RRujb+Gpd2OFYJXGSEbd3faTg8M2kpGCCrVe7SFNoyu8z9NwFItwWMog5aBjX
ODGQrq+kA4ARA6xIqwzF5gP0zr+baT9rWhQdm7Xo9itWdosnbyDLJx1dpEfLuqBX
te3SmifDzedn3Gw73hdNo/+ybw0kHARoK+RmXCTsoDDQw+JsoO9KxZF5Q8QcDELq
2woPNp0Hl+Dm4MkzGnPxv56Qj8ZDViS59syXC0CfGRmu4nzF1Rw+0qn5
=/WlE
-----END PGP SIGNATURE-----
Merge tag 'ceph-for-6.6-rc1' of https://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"Mixed with some fixes and cleanups, this brings in reasonably complete
fscrypt support to CephFS! The list of things which don't work with
encryption should be fairly short, mostly around the edges: fallocate
(not supported well in CephFS to begin with), copy_file_range
(requires re-encryption), non-default striping patterns.
This was a multi-year effort principally by Jeff Layton with
assistance from Xiubo Li, Luís Henriques and others, including several
dependant changes in the MDS, netfs helper library and fscrypt
framework itself"
* tag 'ceph-for-6.6-rc1' of https://github.com/ceph/ceph-client: (53 commits)
ceph: make num_fwd and num_retry to __u32
ceph: make members in struct ceph_mds_request_args_ext a union
rbd: use list_for_each_entry() helper
libceph: do not include crypto/algapi.h
ceph: switch ceph_lookup/atomic_open() to use new fscrypt helper
ceph: fix updating i_truncate_pagecache_size for fscrypt
ceph: wait for OSD requests' callbacks to finish when unmounting
ceph: drop messages from MDS when unmounting
ceph: update documentation regarding snapshot naming limitations
ceph: prevent snapshot creation in encrypted locked directories
ceph: add support for encrypted snapshot names
ceph: invalidate pages when doing direct/sync writes
ceph: plumb in decryption during reads
ceph: add encryption support to writepage and writepages
ceph: add read/modify/write to ceph_sync_write
ceph: align data in pages in ceph_sync_write
ceph: don't use special DIO path for encrypted inodes
ceph: add truncate size handling support for fscrypt
ceph: add object version support for sync read
libceph: allow ceph_osdc_new_request to accept a multi-op read
...
Mostafa reports that commit d232606773 ("arm64/sysreg: refactor
deprecated strncpy") breaks our early command-line parsing because the
original code is working on space-delimited substrings rather than
NUL-terminated strings.
Rather than simply reverting the broken conversion patch, replace the
strscpy() with a simple memcpy() with an explicit NUL-termination of the
result.
Reported-by: Mostafa Saleh <smostafa@google.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Fixes: d232606773 ("arm64/sysreg: refactor deprecated strncpy")
Signed-off-by: Justin Stitt <justinstitt@google.com>
Link: https://lore.kernel.org/r/20230905-strncpy-arch-arm64-v4-1-bc4b14ddfaef@google.com
Link: https://lore.kernel.org/r/20230831162227.2307863-1-smostafa@google.com
Signed-off-by: Will Deacon <will@kernel.org>
- a new driver for Azoteq IQS7210A/7211A/E touch controllers
- support for Azoteq IQS7222D variant added to iqs7222 driver
- support for touch keys functionality added to Melfas MMS114 driver
- new hardware IDs added to exc3000 and Goodix drivers
- xpad driver gained support for GameSir T4 Kaleid Controller
- a fix for xpad driver to properly support some third-party
controllers that need a magic packet to start properly
- a fix for psmouse driver to more reliably switch to RMI4 mode
on devices that use native RMI4/SMbus protocol
- a quirk for i8042 for TUXEDO Gemini 17 Gen1/Clevo PD70PN laptops
- multiple drivers have been updated to make use of devm and other
newer APIs such as dev_err_probe(), devm_regulator_get_enable(),
and others.
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQST2eWILY88ieB2DOtAj56VGEWXnAUCZPeTEAAKCRBAj56VGEWX
nKzYAPwJ7ctpjx11opQrxAz83mW2NSuEI+v3vodpRfqO3DewvQD/QnspSzUuTSWv
hWSQ1uagKZm4FqeJPDowVrU1E9Lq9Aw=
=z9DZ
-----END PGP SIGNATURE-----
Merge tag 'input-for-v6.6-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
- a new driver for Azoteq IQS7210A/7211A/E touch controllers
- support for Azoteq IQS7222D variant added to iqs7222 driver
- support for touch keys functionality added to Melfas MMS114 driver
- new hardware IDs added to exc3000 and Goodix drivers
- xpad driver gained support for GameSir T4 Kaleid Controller
- a fix for xpad driver to properly support some third-party
controllers that need a magic packet to start properly
- a fix for psmouse driver to more reliably switch to RMI4 mode on
devices that use native RMI4/SMbus protocol
- a quirk for i8042 for TUXEDO Gemini 17 Gen1/Clevo PD70PN laptops
- multiple drivers have been updated to make use of devm and other
newer APIs such as dev_err_probe(), devm_regulator_get_enable(), and
others.
* tag 'input-for-v6.6-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (83 commits)
Input: goodix - add support for ACPI ID GDX9110
Input: rpckbd - fix the return value handle for platform_get_irq()
Input: tca6416-keypad - switch to using input core's polling features
Input: tca6416-keypad - convert to use devm_* api
Input: tca6416-keypad - fix interrupt enable disbalance
Input: tca6416-keypad - rely on I2C core to set up suspend/resume
Input: tca6416-keypad - always expect proper IRQ number in i2c client
Input: lm8323 - convert to use devm_* api
Input: lm8323 - rely on device core to create kp_disable attribute
Input: qt2160 - convert to use devm_* api
Input: qt2160 - do not hard code interrupt trigger
Input: qt2160 - switch to using threaded interrupt handler
Input: qt2160 - tweak check for i2c adapter functionality
Input: psmouse - add delay when deactivating for SMBus mode
Input: mcs-touchkey - fix uninitialized use of error in mcs_touchkey_probe()
Input: qt1070 - convert to use devm_* api
Input: mcs-touchkey - convert to use devm_* api
Input: amikbd - convert to use devm_* api
Input: lm8333 - convert to use devm_* api
Input: mms114 - add support for touch keys
...
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.14 (GNU/Linux)
iEYEABECAAYFAmT3b+IACgkQ+iyteGJfRsr0hwCgkfCpOknevjztFcumniR1pREF
/z0AoIrUiPIkeDuyHwZYmILzS0jqHmU5
=OQC4
-----END PGP SIGNATURE-----
Merge tag 'linux-watchdog-6.6-rc1' of git://www.linux-watchdog.org/linux-watchdog
Pull watchdog updates from Wim Van Sebroeck:
- add marvell GTI watchdog driver
- add support for Amlogic-T7 SoCs
- document the IPQ5018 watchdog compatible
- enable COMPILE_TEST for more watchdog device drivers
- core: stop watchdog when executing poweroff command
- other small improvements and fixes
* tag 'linux-watchdog-6.6-rc1' of git://www.linux-watchdog.org/linux-watchdog: (21 commits)
watchdog: Add support for Amlogic-T7 SoCs
watchdog: Add a new struct for Amlogic-GXBB driver
dt-bindings: watchdog: Add support for Amlogic-T7 SoCs
dt-bindings: watchdog: qcom-wdt: document IPQ5018
watchdog: imx2_wdt: Improve dev_crit() message
watchdog: stm32: Drop unnecessary of_match_ptr()
watchdog: sama5d4: readout initial state
watchdog: intel-mid_wdt: add MODULE_ALIAS() to allow auto-load
watchdog: core: stop watchdog when executing poweroff command
watchdog: pm8916_wdt: Remove redundant of_match_ptr()
watchdog: xilinx_wwdt: Use div_u64() in xilinx_wwdt_start()
watchdog: starfive: Remove #ifdef guards for PM related functions
watchdog: s3c2410: Fix potential deadlock on &wdt->lock
watchdog:rit_wdt: Add support for WDIOF_CARDRESET
dt-bindings: watchdog: ti,rti-wdt: Add support for WDIOF_CARDRESET
watchdog: Enable COMPILE_TEST for more drivers
watchdog: advantech_ec_wdt: fix Kconfig dependencies
watchdog: Explicitly include correct DT includes
Watchdog: Add marvell GTI watchdog driver
dt-bindings: watchdog: marvell GTI system watchdog driver
...
The missing IP_SET_HASH_WITH_NET0 macro in ip_set_hash_netportnet can
lead to the use of wrong `CIDR_POS(c)` for calculating array offsets,
which can lead to integer underflow. As a result, it leads to slab
out-of-bound access.
This patch adds back the IP_SET_HASH_WITH_NET0 macro to
ip_set_hash_netportnet to address the issue.
Fixes: 886503f34d ("netfilter: ipset: actually allow allowable CIDR 0 in hash:net,port,net")
Suggested-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Kyle Zeng <zengyhkyle@gmail.com>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
New elements in this transaction might expired before such transaction
ends. Skip sync GC for such elements otherwise commit path might walk
over an already released object. Once transaction is finished, async GC
will collect such expired element.
Fixes: f6c383b8c3 ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
The opt_num field is controlled by user mode and is not currently
validated inside the kernel. An attacker can take advantage of this to
trigger an OOB read and potentially leak information.
BUG: KASAN: slab-out-of-bounds in nf_osf_match_one+0xbed/0xd10 net/netfilter/nfnetlink_osf.c:88
Read of size 2 at addr ffff88804bc64272 by task poc/6431
CPU: 1 PID: 6431 Comm: poc Not tainted 6.0.0-rc4 #1
Call Trace:
nf_osf_match_one+0xbed/0xd10 net/netfilter/nfnetlink_osf.c:88
nf_osf_find+0x186/0x2f0 net/netfilter/nfnetlink_osf.c:281
nft_osf_eval+0x37f/0x590 net/netfilter/nft_osf.c:47
expr_call_ops_eval net/netfilter/nf_tables_core.c:214
nft_do_chain+0x2b0/0x1490 net/netfilter/nf_tables_core.c:264
nft_do_chain_ipv4+0x17c/0x1f0 net/netfilter/nft_chain_filter.c:23
[..]
Also add validation to genre, subtype and version fields.
Fixes: 11eeef41d5 ("netfilter: passive OS fingerprint xtables match")
Reported-by: Lucas Leong <wmliang@infosec.exchange>
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
If priv->len is a multiple of 4, then dst[len / 4] can write past
the destination array which leads to stack corruption.
This construct is necessary to clean the remainder of the register
in case ->len is NOT a multiple of the register size, so make it
conditional just like nft_payload.c does.
The bug was added in 4.1 cycle and then copied/inherited when
tcp/sctp and ip option support was added.
Bug reported by Zero Day Initiative project (ZDI-CAN-21950,
ZDI-CAN-21951, ZDI-CAN-21961).
Fixes: 49499c3e6e ("netfilter: nf_tables: switch registers to 32 bit addressing")
Fixes: 935b7f6430 ("netfilter: nft_exthdr: add TCP option matching")
Fixes: 133dc203d7 ("netfilter: nft_exthdr: Support SCTP chunks")
Fixes: dbb5281a1f ("netfilter: nf_tables: add support for matching IPv4 options")
Signed-off-by: Florian Westphal <fw@strlen.de>
- Ensure correct includes are present and remove some that are not required
- Drop redundant of_match_ptr() call to cast pointer to NULL
- Bug Fixes
- Revert to old (expected) behaviour of initialising PWM state on first brightness change
- Correctly handle / propagate errors
- Fix 'sometimes-uninitialised' issues
-----BEGIN PGP SIGNATURE-----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=5vB4
-----END PGP SIGNATURE-----
Merge tag 'backlight-next-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
"New Functionality:
- Ensure correct includes are present and remove some that are not
required
- Drop redundant of_match_ptr() call to cast pointer to NULL
Bug Fixes:
- Revert to old (expected) behaviour of initialising PWM state on
first brightness change
- Correctly handle / propagate errors
- Fix 'sometimes-uninitialised' issues"
* tag 'backlight-next-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
backlight: led_bl: Remove redundant of_match_ptr()
backlight: lp855x: Drop ret variable in brightness change function
backlight: gpio_backlight: Drop output GPIO direction check for initial power state
backlight: lp855x: Catch errors when changing brightness
backlight: lp855x: Initialize PWM state on first brightness change
backlight: qcom-wled: Explicitly include correct DT includes
Commit f569143935 ("gpio: zynq: fix zynqmp_gpio not an immutable chip
warning") ditched the open-coded resource allocation handlers in favor
of the generic ones. These generic handlers don't maintain the PM
runtime anymore, which causes a regression in that level IRQs are no
longer reported.
Restore the original handlers to fix this.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Fixes: f569143935 ("gpio: zynq: fix zynqmp_gpio not an immutable chip warning")
Cc: stable@kernel.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
1/8 of kernel addresses reserved for shadow memory. But for LoongArch,
There are a lot of holes between different segments and valid address
space (256T available) is insufficient to map all these segments to kasan
shadow memory with the common formula provided by kasan core, saying
(addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET
So LoongArch has a arch-specific mapping formula, different segments are
mapped individually, and only limited space lengths of these specific
segments are mapped to shadow.
At early boot stage the whole shadow region populated with just one
physical page (kasan_early_shadow_page). Later, this page is reused as
readonly zero shadow for some memory that kasan currently don't track.
After mapping the physical memory, pages for shadow memory are allocated
and mapped.
Functions like memset()/memcpy()/memmove() do a lot of memory accesses.
If bad pointer passed to one of these function it is important to be
caught. Compiler's instrumentation cannot do this since these functions
are written in assembly.
KASan replaces memory functions with manually instrumented variants.
Original functions declared as weak symbols so strong definitions in
mm/kasan/kasan.c could replace them. Original functions have aliases
with '__' prefix in names, so we could call non-instrumented variant
if needed.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Modified relocate_kernel() doesn't return new kernel's entry point but
the random_offset. In this way we share the start_kernel() processing
with the normal kernel, which avoids calling 'jr a0' directly and allows
some other operations (e.g, kasan_early_init) before start_kernel() when
KASLR (CONFIG_RANDOMIZE_BASE) is turned on.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LoongArch populates pmd/pud with invalid_pmd_table/invalid_pud_table in
pagetable_init, So pmd_init/pud_init(p) is required, define them as __weak
in mm/kasan/init.c, like mm/sparse-vmemmap.c.
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
MIPS, LoongArch and some other architectures have many holes between
different segments and the valid address space (256T available) is
insufficient to map all these segments to kasan shadow memory with the
common formula provided by kasan core. So we need architecture specific
mapping formulas to ensure different segments are mapped individually,
and only limited space lengths of those specific segments are mapped to
shadow.
Therefore, when the incoming address is converted to a shadow, we need
to add a condition to determine whether it is valid.
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The LoongArch architecture is quite different from other architectures.
When the allocating of KFENCE itself is done, it is mapped to the direct
mapping configuration window [1] by default on LoongArch. It means that
it is not possible to use the page table mapped mode which required by
the KFENCE system and therefore it should be remapped to the appropriate
region.
This patch adds architecture specific implementation details for KFENCE.
In particular, this implements the required interface in <asm/kfence.h>.
Tested this patch by running the testcases and all passed.
[1] https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#virtual-address-space-and-address-translation-mode
Signed-off-by: Enze Li <lienze@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Currently, arch_stack_walk() can only get the full stack information
including NMI. This is because the implementation of arch_stack_walk()
is forced to ignore the information passed by the regs parameter and use
the current stack information instead.
For some detection systems like KFENCE, only partial stack information
is needed. In particular, the stack frame where the interrupt occurred.
To support KFENCE, this patch modifies the implementation of the
arch_stack_walk() function so that if this function is called with the
regs argument passed, it retains all the stack information in regs and
uses it to provide accurate information.
Before this patch:
[ 1.531195 ] ==================================================================
[ 1.531442 ] BUG: KFENCE: out-of-bounds read in stack_trace_save_regs+0x48/0x6c
[ 1.531442 ]
[ 1.531900 ] Out-of-bounds read at 0xffff800012267fff (1B left of kfence-#12):
[ 1.532046 ] stack_trace_save_regs+0x48/0x6c
[ 1.532169 ] kfence_report_error+0xa4/0x528
[ 1.532276 ] kfence_handle_page_fault+0x124/0x270
[ 1.532388 ] no_context+0x50/0x94
[ 1.532453 ] do_page_fault+0x1a8/0x36c
[ 1.532524 ] tlb_do_page_fault_0+0x118/0x1b4
[ 1.532623 ] test_out_of_bounds_read+0xa0/0x1d8
[ 1.532745 ] kunit_generic_run_threadfn_adapter+0x1c/0x28
[ 1.532854 ] kthread+0x124/0x130
[ 1.532922 ] ret_from_kernel_thread+0xc/0xa4
<snip>
After this patch:
[ 1.320220 ] ==================================================================
[ 1.320401 ] BUG: KFENCE: out-of-bounds read in test_out_of_bounds_read+0xa8/0x1d8
[ 1.320401 ]
[ 1.320898 ] Out-of-bounds read at 0xffff800012257fff (1B left of kfence-#10):
[ 1.321134 ] test_out_of_bounds_read+0xa8/0x1d8
[ 1.321264 ] kunit_generic_run_threadfn_adapter+0x1c/0x28
[ 1.321392 ] kthread+0x124/0x130
[ 1.321459 ] ret_from_kernel_thread+0xc/0xa4
<snip>
Suggested-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Enze Li <lienze@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
According to LoongArch documentations, there are two types of address
translation modes: direct mapped address translation mode (DMW mode) and
page table mapped address translation mode (TLB mode).
Currently, virt_to_page() only supports direct mapped mode. This patch
determines which mode is used, and adds corresponding handling functions
for both modes.
For more details on the two modes, see [1].
[1] https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#virtual-address-space-and-address-translation-mode
Signed-off-by: Enze Li <lienze@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The LoongArch architecture is different from other architectures. It
needs to update __kfence_pool during arch_kfence_init_pool().
This patch modifies the assignment location of the local variable addr
in the kfence_init_pool() function to support the case of updating
__kfence_pool in arch_kfence_init_pool().
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Enze Li <lienze@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to the LoongArch Kconfig. And
also disable instrumentation of vdso.
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Provide kaslr_offset() to get the kernel offset when KASLR is enabled.
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
KGDB is intended to be used as a source level debugger for the Linux
kernel. It is used along with gdb to debug a Linux kernel. GDB can be
used to "break in" to the kernel to inspect memory, variables and regs
similar to the way an application developer would use GDB to debug an
application. KDB is a frontend of KGDB which is similar to GDB.
By now, in addition to the generic KGDB features, the LoongArch KGDB
implements the following features:
- Hardware breakpoints/watchpoints;
- Software single-step support for KDB.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn> # Framework & CoreFeature
Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> # BreakPoint & SingleStep
Signed-off-by: Hui Li <lihui@loongson.cn> # Some Minor Improvements
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> # Some Build Error Fixes
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Loongson Binary Translation (LBT) is used to accelerate binary translation,
which contains 4 scratch registers (scr0 to scr3), x86/ARM eflags (eflags)
and x87 fpu stack pointer (ftop).
This patch support kernel to save/restore these registers, handle the LBT
exception and maintain sigcontext.
Signed-off-by: Qi Hu <huqi@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Similar to the syndrome calculation, the recovery algorithms also work
on 64 bytes at a time to align with the L1 cache line size of current
and future LoongArch cores (that we care about). Which means
unrolled-by-4 LSX and unrolled-by-2 LASX code.
The assembly is originally based on the x86 SSSE3/AVX2 ports, but
register allocation has been redone to take advantage of LSX/LASX's 32
vector registers, and instruction sequence has been optimized to suit
(e.g. LoongArch can perform per-byte srl and andi on vectors, but x86
cannot).
Performance numbers measured by instrumenting the raid6test code, on a
3A5000 system clocked at 2.5GHz:
> lasx 2data: 354.987 MiB/s
> lasx datap: 350.430 MiB/s
> lsx 2data: 340.026 MiB/s
> lsx datap: 337.318 MiB/s
> intx1 2data: 164.280 MiB/s
> intx1 datap: 187.966 MiB/s
Because recovery algorithms are chosen solely based on priority and
availability, lasx is marked as priority 2 and lsx priority 1. At least
for the current generation of LoongArch micro-architectures, LASX should
always be faster than LSX whenever supported, and have similar power
consumption characteristics (because the only known LASX-capable uarch,
the LA464, always compute the full 256-bit result for vector ops).
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The algorithms work on 64 bytes at a time, which is the L1 cache line
size of all current and future LoongArch cores (that we care about), as
confirmed by Huacai. The code is based on the generic int.uc algorithm,
unrolled 4 times for LSX and 2 times for LASX. Further unrolling does
not meaningfully improve the performance according to experiments.
Performance numbers measured during system boot on a 3A5000 @ 2.5GHz:
> raid6: lasx gen() 12726 MB/s
> raid6: lsx gen() 10001 MB/s
> raid6: int64x8 gen() 2876 MB/s
> raid6: int64x4 gen() 3867 MB/s
> raid6: int64x2 gen() 2531 MB/s
> raid6: int64x1 gen() 1945 MB/s
Comparison of xor() speeds (from different boots but meaningful anyway):
> lasx: 11226 MB/s
> lsx: 6395 MB/s
> int64x4: 2147 MB/s
Performance as measured by raid6test:
> raid6: lasx gen() 25109 MB/s
> raid6: lsx gen() 13233 MB/s
> raid6: int64x8 gen() 4164 MB/s
> raid6: int64x4 gen() 6005 MB/s
> raid6: int64x2 gen() 5781 MB/s
> raid6: int64x1 gen() 4119 MB/s
> raid6: using algorithm lasx gen() 25109 MB/s
> raid6: .... xor() 14439 MB/s, rmw enabled
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Add LSX and LASX implementations of xor operations, operating on 64
bytes (one L1 cache line) at a time, for a balance between memory
utilization and instruction mix. Huacai confirmed that all future
LoongArch implementations by Loongson (that we care) will likely also
feature 64-byte cache lines, and experiments show no throughput
improvement with further unrolling.
Performance numbers measured during system boot on a 3A5000 @ 2.5GHz:
> 8regs : 12702 MB/sec
> 8regs_prefetch : 10920 MB/sec
> 32regs : 12686 MB/sec
> 32regs_prefetch : 10918 MB/sec
> lsx : 17589 MB/sec
> lasx : 26116 MB/sec
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Allow usage of LSX/LASX in the kernel by extending kernel_fpu_begin()
and kernel_fpu_end().
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The initial aim is to silence the following objtool warnings:
arch/loongarch/kernel/fpu.o: warning: objtool: _save_fp_context() falls through to next function fault()
arch/loongarch/kernel/fpu.o: warning: objtool: _restore_fp_context() falls through to next function fault()
arch/loongarch/kernel/fpu.o: warning: objtool: _save_lsx_context() falls through to next function fault()
arch/loongarch/kernel/fpu.o: warning: objtool: _restore_lsx_context() falls through to next function fault()
arch/loongarch/kernel/fpu.o: warning: objtool: _save_lasx_context() falls through to next function fault()
arch/loongarch/kernel/fpu.o: warning: objtool: _restore_lasx_context() falls through to next function fault()
Currently, SYM_FUNC_START()/SYM_FUNC_END() defines the symbol 'fault' as
SYM_T_FUNC which is STT_FUNC, the objtool warnings are generated through
the following code:
tools/objtool/include/objtool/check.h:
static inline struct symbol *insn_func(struct instruction *insn)
{
struct symbol *sym = insn->sym;
if (sym && sym->type != STT_FUNC)
sym = NULL;
return sym;
}
tools/objtool/check.c:
static int validate_branch(struct objtool_file *file, struct symbol *func,
struct instruction *insn, struct insn_state state)
{
...
if (func && insn_func(insn) && func != insn_func(insn)->pfunc) {
...
WARN("%s() falls through to next function %s()",
func->name, insn_func(insn)->name);
return 1;
}
...
}
We can see that the fixup can be a local label in the following code:
arch/loongarch/include/asm/asm-extable.h:
.pushsection __ex_table, "a"; \
.balign 4; \
.long ((insn) - .); \
.long ((fixup) - .); \
.short (type); \
.short (data); \
.popsection;
.macro _asm_extable, insn, fixup
__ASM_EXTABLE_RAW(\insn, \fixup, EX_TYPE_FIXUP, 0)
.endm
Like arch/loongarch/lib/*.S, just define the symbol 'fault' as a local
label in fpu.S.
Before:
$ readelf -s arch/loongarch/kernel/fpu.o | awk -F: /fault/'{print $2}'
000000000000053c 8 FUNC GLOBAL DEFAULT 1 fault
After:
$ readelf -s arch/loongarch/kernel/fpu.o | awk -F: /fault/'{print $2}'
000000000000053c 0 NOTYPE LOCAL DEFAULT 1 .L_fpu_fault
Co-developed-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The {copy, clear}_user function should returns number of bytes that
could not be {copied, cleared}. So, try to {copy, clear} byte by byte
when ld.{d,w,h} and st.{d,w,h} trapped into an exception.
Reviewed-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Weihao Li <liweihao@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
On LoongArch system, there is only one page needed for zero page (no
cache synonyms), and there is no COLOR_ZERO_PAGE, so zero_page_mask is
useless and the macro __HAVE_COLOR_ZERO_PAGE is not necessary.
Like other popular architectures, It is simpler to define the zero page
in kernel BSS code segment rather than dynamically allocate.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Function pcpu_populate_pte() and fixmap_pte() are similar, they populate
one page from kernel address space. And there is confusion between pgd
and p4d in the function fixmap_pte(), such as pgd_none() always returns
zero. This patch introduces a unified function populate_kernel_pte() and
then replaces pcpu_populate_pte() and fixmap_pte().
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Do some code improvements in function pcpu_populate_pte():
1. Add memory allocation failure handling;
2. Replace pgd_populate() with p4d_populate(), it will be useful if
there are four-level page tables.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Both shm_align_mask and SHMLBA want to avoid cache alias. But they are
inconsistent: shm_align_mask is (PAGE_SIZE - 1) while SHMLBA is SZ_64K,
but PAGE_SIZE is not always equal to SZ_64K.
This may cause problems when shmat() twice. Fix this problem by removing
shm_align_mask and using SHMLBA (strictly SHMLBA - 1) instead.
Reported-by: Jiantao Shan <shanjiantao@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When I do LTP test, LTP test case ksm06 caused panic at
break_ksm_pmd_entry
-> pmd_leaf (Huge page table but False)
-> pte_present (panic)
The reason is pmd_leaf() is not defined, So like commit 501b810467
("mips: mm: add p?d_leaf() definitions") add p?d_leaf() definition for
LoongArch.
Fixes: 09cfefb7fa ("LoongArch: Add memory management")
Cc: stable@vger.kernel.org
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When building with CONFIG_LTO_CLANG_FULL, there are several errors due
to the way that parse_r is defined with an __asm__ statement in a
header:
ld.lld: error: ld-temp.o <inline asm>:105:1: macro 'parse_r' is already defined
.macro parse_r var r
^
This was an issue for arch/mips as well, which was resolved by commit
67512a8cf5 ("MIPS: Avoid macro redefinitions").
However, parse_r is unused in arch/loongarch after commit 83d8b38967
("LoongArch: Simplify the invtlb wrappers"), so doing the same change
does not make much sense now. Just remove parse_r (and parse_v, which
is also unused) to resolve the redefinition error. If it needs to be
brought back due to an actual use, it should be brought back with the
same changes as the aforementioned arch/mips commit.
Closes: https://github.com/ClangBuiltLinux/linux/issues/1924
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
bvec_set_page has the following signature:
static inline void bvec_set_page(struct bio_vec *bv, struct page *page,
unsigned int len, unsigned int offset)
However, the usage in DRBD swaps the len and offset parameters. This
leads to a bvec with length=0 instead of the intended length=4096, which
causes sock_sendmsg to return -EIO.
This leaves DRBD unable to transmit any pages and thus completely
broken.
Swapping the parameters fixes the regression.
Fixes: eeac7405c7 ("drbd: Use sendmsg(MSG_SPLICE_PAGES) rather than sendpage()")
Reported-by: Serguei Ivantsov <manowar@gsc-game.com>
Link: https://lore.kernel.org/regressions/CAKH+VT3YLmAn0Y8=q37UTDShqxDLsqPcQ4hBMzY7HPn7zNx+RQ@mail.gmail.com/
Cc: stable@vger.kernel.org
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://lore.kernel.org/r/20230906133034.948817-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no need to unpin the added page when adding it to the bio fails
as that is done by the loop below. Instead we want to unpin it when adding
a single page to the bio more than once as bio_release_pages will only
unpin it once.
Fixes: d1916c86cc ("block: move same page handling from __bio_add_pc_page to the callers")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20230905124731.328255-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use bpf_jit_binary_pack_alloc() for memory management of JIT binaries in
RISCV BPF JIT. The bpf_jit_binary_pack_alloc creates a pair of RW and RX
buffers. The JIT writes the program into the RW buffer. When the JIT is
done, the program is copied to the final RX buffer with
bpf_jit_binary_pack_finalize.
Implement bpf_arch_text_copy() and bpf_arch_text_invalidate() for RISCV
JIT as these functions are required by bpf_jit_binary_pack allocator.
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Reviewed-by: Song Liu <song@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20230831131229.497941-5-puranjay12@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The BPF JIT needs to write invalid instructions to RX regions of memory to
invalidate removed BPF programs. This needs a function like memset() that
can work with RX memory.
Implement patch_text_set_nosync() which is similar to text_poke_set() of
x86.
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20230831131229.497941-4-puranjay12@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The patch_insn_write() function currently doesn't work for multiple pages
of instructions, therefore patch_text_nosync() will fail with a page fault
if called with lengths spanning multiple pages.
This commit extends the patch_insn_write() function to support multiple
pages by copying at max 2 pages at a time in a loop. This implementation
is similar to text_poke_copy() function of x86.
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20230831131229.497941-3-puranjay12@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The bpf_prog_pack allocator currently uses module_alloc() and
module_memfree() to allocate and free memory. This is not portable
because different architectures use different methods for allocating
memory for BPF programs. Like ARM64 and riscv use vmalloc()/vfree().
Use bpf_jit_alloc_exec() and bpf_jit_free_exec() for memory management
in bpf_prog_pack allocator. Other architectures can override these with
their implementation and will be able to use bpf_prog_pack directly.
On architectures that don't override bpf_jit_alloc/free_exec() this is
basically a NOP.
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20230831131229.497941-2-puranjay12@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The commit c83597fa5d ("bpf: Refactor some inode/task/sk storage functions
for reuse"), refactored the bpf_{sk,task,inode}_storage_free() into
bpf_local_storage_unlink_nolock() which then later renamed to
bpf_local_storage_destroy(). The commit accidentally passed the
"bool uncharge_mem = false" argument to bpf_selem_unlink_storage_nolock()
which then stopped the uncharge from happening to the sk->sk_omem_alloc.
This missing uncharge only happens when the sk is going away (during
__sk_destruct).
This patch fixes it by always passing "uncharge_mem = true". It is a
noop to the task/inode/cgroup storage because they do not have the
map_local_storage_(un)charge enabled in the map_ops. A followup patch
will be done in bpf-next to remove the uncharge_mem argument.
A selftest is added in the next patch.
Fixes: c83597fa5d ("bpf: Refactor some inode/task/sk storage functions for reuse")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-3-martin.lau@linux.dev
'./test_progs -t test_local_storage' reported a splat:
[ 27.137569] =============================
[ 27.138122] [ BUG: Invalid wait context ]
[ 27.138650] 6.5.0-03980-gd11ae1b16b0a #247 Tainted: G O
[ 27.139542] -----------------------------
[ 27.140106] test_progs/1729 is trying to lock:
[ 27.140713] ffff8883ef047b88 (stock_lock){-.-.}-{3:3}, at: local_lock_acquire+0x9/0x130
[ 27.141834] other info that might help us debug this:
[ 27.142437] context-{5:5}
[ 27.142856] 2 locks held by test_progs/1729:
[ 27.143352] #0: ffffffff84bcd9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x40
[ 27.144492] #1: ffff888107deb2c0 (&storage->lock){..-.}-{2:2}, at: bpf_local_storage_update+0x39e/0x8e0
[ 27.145855] stack backtrace:
[ 27.146274] CPU: 0 PID: 1729 Comm: test_progs Tainted: G O 6.5.0-03980-gd11ae1b16b0a #247
[ 27.147550] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 27.149127] Call Trace:
[ 27.149490] <TASK>
[ 27.149867] dump_stack_lvl+0x130/0x1d0
[ 27.152609] dump_stack+0x14/0x20
[ 27.153131] __lock_acquire+0x1657/0x2220
[ 27.153677] lock_acquire+0x1b8/0x510
[ 27.157908] local_lock_acquire+0x29/0x130
[ 27.159048] obj_cgroup_charge+0xf4/0x3c0
[ 27.160794] slab_pre_alloc_hook+0x28e/0x2b0
[ 27.161931] __kmem_cache_alloc_node+0x51/0x210
[ 27.163557] __kmalloc+0xaa/0x210
[ 27.164593] bpf_map_kzalloc+0xbc/0x170
[ 27.165147] bpf_selem_alloc+0x130/0x510
[ 27.166295] bpf_local_storage_update+0x5aa/0x8e0
[ 27.167042] bpf_fd_sk_storage_update_elem+0xdb/0x1a0
[ 27.169199] bpf_map_update_value+0x415/0x4f0
[ 27.169871] map_update_elem+0x413/0x550
[ 27.170330] __sys_bpf+0x5e9/0x640
[ 27.174065] __x64_sys_bpf+0x80/0x90
[ 27.174568] do_syscall_64+0x48/0xa0
[ 27.175201] entry_SYSCALL_64_after_hwframe+0x6e/0xd8
[ 27.175932] RIP: 0033:0x7effb40e41ad
[ 27.176357] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d8
[ 27.179028] RSP: 002b:00007ffe64c21fc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000141
[ 27.180088] RAX: ffffffffffffffda RBX: 00007ffe64c22768 RCX: 00007effb40e41ad
[ 27.181082] RDX: 0000000000000020 RSI: 00007ffe64c22008 RDI: 0000000000000002
[ 27.182030] RBP: 00007ffe64c21ff0 R08: 0000000000000000 R09: 00007ffe64c22788
[ 27.183038] R10: 0000000000000064 R11: 0000000000000202 R12: 0000000000000000
[ 27.184006] R13: 00007ffe64c22788 R14: 00007effb42a1000 R15: 0000000000000000
[ 27.184958] </TASK>
It complains about acquiring a local_lock while holding a raw_spin_lock.
It means it should not allocate memory while holding a raw_spin_lock
since it is not safe for RT.
raw_spin_lock is needed because bpf_local_storage supports tracing
context. In particular for task local storage, it is easy to
get a "current" task PTR_TO_BTF_ID in tracing bpf prog.
However, task (and cgroup) local storage has already been moved to
bpf mem allocator which can be used after raw_spin_lock.
The splat is for the sk storage. For sk (and inode) storage,
it has not been moved to bpf mem allocator. Using raw_spin_lock or not,
kzalloc(GFP_ATOMIC) could theoretically be unsafe in tracing context.
However, the local storage helper requires a verifier accepted
sk pointer (PTR_TO_BTF_ID), it is hypothetical if that (mean running
a bpf prog in a kzalloc unsafe context and also able to hold a verifier
accepted sk pointer) could happen.
This patch avoids kzalloc after raw_spin_lock to silent the splat.
There is an existing kzalloc before the raw_spin_lock. At that point,
a kzalloc is very likely required because a lookup has just been done
before. Thus, this patch always does the kzalloc before acquiring
the raw_spin_lock and remove the later kzalloc usage after the
raw_spin_lock. After this change, it will have a charge and then
uncharge during the syscall bpf_map_update_elem() code path.
This patch opts for simplicity and not continue the old
optimization to save one charge and uncharge.
This issue is dated back to the very first commit of bpf_sk_storage
which had been refactored multiple times to create task, inode, and
cgroup storage. This patch uses a Fixes tag with a more recent
commit that should be easier to do backport.
Fixes: b00fa38a9c ("bpf: Enable non-atomic allocations in local storage")
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230901231129.578493-2-martin.lau@linux.dev