203 Commits

Author SHA1 Message Date
Jiantao Shan
ba9bcc0e58 LoongArch: Fix access error when read fault on a write-only VMA
commit efb44ff64c95340b06331fc48634b99efc9dd77c upstream.

As with most architectures, allow handling of read faults in VMAs that
have VM_WRITE but without VM_READ (WRITE implies READ).

Otherwise, reading before writing a write-only memory will error while
reading after writing everything is fine.

BTW, move the VM_EXEC judgement before VM_READ/VM_WRITE to make logic a
little clearer.

Cc: stable@vger.kernel.org
Fixes: 09cfefb7fa70c3af01 ("LoongArch: Add memory management")
Signed-off-by: Jiantao Shan <shanjiantao@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-02 16:29:28 +02:00
Huacai Chen
94021d1d2b LoongArch: Fix callchain parse error with kernel tracepoint events
commit d3119bc985fb645ad3b2a9cf9952c1d56d9daaa3 upstream.

In order to fix perf's callchain parse error for LoongArch, we implement
perf_arch_fetch_caller_regs() which fills several necessary registers
used for callchain unwinding, including sp, fp, and era. This is similar
to the following commits.

commit b3eac0265bf6:
("arm: perf: Fix callchain parse error with kernel tracepoint events")

commit 5b09a094f2fb:
("arm64: perf: Fix callchain parse error with kernel tracepoint events")

commit 9a7e8ec0d4cc:
("riscv: perf: Fix callchain parse error with kernel tracepoint events")

Test with commands:

 perf record -e sched:sched_switch -g --call-graph dwarf
 perf report

Without this patch:

 Children      Self  Command        Shared Object      Symbol
 ........  ........  .............  .................  ....................

 43.41%    43.41%  swapper          [unknown]          [k] 0000000000000000

 10.94%    10.94%  loong-container  [unknown]          [k] 0000000000000000
         |
         |--5.98%--0x12006ba38
         |
         |--2.56%--0x12006bb84
         |
          --2.40%--0x12006b6b8

With this patch, callchain can be parsed correctly:

 Children      Self  Command        Shared Object      Symbol
 ........  ........  .............  .................  ....................

 47.57%    47.57%  swapper          [kernel.vmlinux]   [k] __schedule
         |
         ---__schedule

 26.76%    26.76%  loong-container  [kernel.vmlinux]   [k] __schedule
         |
         |--13.78%--0x12006ba38
         |          |
         |          |--9.19%--__schedule
         |          |
         |           --4.59%--handle_syscall
         |                     do_syscall
         |                     sys_futex
         |                     do_futex
         |                     futex_wait
         |                     futex_wait_queue_me
         |                     hrtimer_start_range_ns
         |                     __schedule
         |
         |--8.38%--0x12006bb84
         |          handle_syscall
         |          do_syscall
         |          sys_epoll_pwait
         |          do_epoll_wait
         |          schedule_hrtimeout_range_clock
         |          hrtimer_start_range_ns
         |          __schedule
         |
          --4.59%--0x12006b6b8
                    handle_syscall
                    do_syscall
                    sys_nanosleep
                    hrtimer_nanosleep
                    do_nanosleep
                    hrtimer_start_range_ns
                    __schedule

Cc: stable@vger.kernel.org
Fixes: b37042b2bb7cd751f0 ("LoongArch: Add perf events support")
Reported-by: Youling Tang <tangyouling@kylinos.cn>
Suggested-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-02 16:29:28 +02:00
Huacai Chen
97cd43ba82 LoongArch: Define the __io_aw() hook as mmiowb()
[ Upstream commit 9c68ece8b2a5c5ff9b2fcaea923dd73efeb174cd ]

Commit fb24ea52f78e0d595852e ("drivers: Remove explicit invocations of
mmiowb()") remove all mmiowb() in drivers, but it says:

"NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation."

The mmio in radeon_ring_commit() is protected by a mutex rather than a
spinlock, but in the mutex fastpath it behaves similar to spinlock. We
can add mmiowb() calls in the radeon driver but the maintainer says he
doesn't like such a workaround, and radeon is not the only example of
mutex protected mmio.

So we should extend the mmiowb tracking system from spinlock to mutex,
and maybe other locking primitives. This is not easy and error prone, so
we solve it in the architectural code, by simply defining the __io_aw()
hook as mmiowb(). And we no longer need to override queued_spin_unlock()
so use the generic definition.

Without this, we get such an error when run 'glxgears' on weak ordering
architectures such as LoongArch:

radeon 0000:04:00.0: ring 0 stalled for more than 10324msec
radeon 0000:04:00.0: ring 3 stalled for more than 10240msec
radeon 0000:04:00.0: GPU lockup (current fence id 0x000000000001f412 last fence id 0x000000000001f414 on ring 3)
radeon 0000:04:00.0: GPU lockup (current fence id 0x000000000000f940 last fence id 0x000000000000f941 on ring 0)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)

Link: https://lore.kernel.org/dri-devel/29df7e26-d7a8-4f67-b988-44353c4270ac@amd.com/T/#t
Link: https://lore.kernel.org/linux-arch/20240301130532.3953167-1-chenhuacai@loongson.cn/T/#t
Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:19:38 +02:00
Huacai Chen
77eae2d257 LoongArch: Change __my_cpu_offset definition to avoid mis-optimization
[ Upstream commit c87e12e0e8c1241410e758e181ca6bf23efa5b5b ]

From GCC commit 3f13154553f8546a ("df-scan: remove ad-hoc handling of
global regs in asms"), global registers will no longer be forced to add
to the def-use chain. Then current_thread_info(), current_stack_pointer
and __my_cpu_offset may be lifted out of the loop because they are no
longer treated as "volatile variables".

This optimization is still correct for the current_thread_info() and
current_stack_pointer usages because they are associated to a thread.
However it is wrong for __my_cpu_offset because it is associated to a
CPU rather than a thread: if the thread migrates to a different CPU in
the loop, __my_cpu_offset should be changed.

Change __my_cpu_offset definition to treat it as a "volatile variable",
in order to avoid such a mis-optimization.

Cc: stable@vger.kernel.org
Reported-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Reported-by: Miao Wang <shankerwangmiao@gmail.com>
Signed-off-by: Xing Li <lixing@loongson.cn>
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Rui Wang <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-03 15:19:38 +02:00
Huacai Chen
a262b78dd0 LoongArch: Disable IRQ before init_fn() for nonboot CPUs
commit 1001db6c42e4012b55e5ee19405490f23e033b5a upstream.

Disable IRQ before init_fn() for nonboot CPUs when hotplug, in order to
silence such warnings (and also avoid potential errors due to unexpected
interrupts):

WARNING: CPU: 1 PID: 0 at kernel/rcu/tree.c:4503 rcu_cpu_starting+0x214/0x280
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.6.17+ #1198
pc 90000000048e3334 ra 90000000047bd56c tp 900000010039c000 sp 900000010039fdd0
a0 0000000000000001 a1 0000000000000006 a2 900000000802c040 a3 0000000000000000
a4 0000000000000001 a5 0000000000000004 a6 0000000000000000 a7 90000000048e3f4c
t0 0000000000000001 t1 9000000005c70968 t2 0000000004000000 t3 000000000005e56e
t4 00000000000002e4 t5 0000000000001000 t6 ffffffff80000000 t7 0000000000040000
t8 9000000007931638 u0 0000000000000006 s9 0000000000000004 s0 0000000000000001
s1 9000000006356ac0 s2 9000000007244000 s3 0000000000000001 s4 0000000000000001
s5 900000000636f000 s6 7fffffffffffffff s7 9000000002123940 s8 9000000001ca55f8
   ra: 90000000047bd56c tlb_init+0x24c/0x528
  ERA: 90000000048e3334 rcu_cpu_starting+0x214/0x280
 CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
 PRMD: 00000000 (PPLV0 -PIE -PWE)
 EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
 ECFG: 00071000 (LIE=12 VS=7)
ESTAT: 000c0000 [BRK] (IS= ECode=12 EsubCode=0)
 PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.6.17+ #1198
Stack : 0000000000000000 9000000006375000 9000000005b61878 900000010039c000
        900000010039fa30 0000000000000000 900000010039fa38 900000000619a140
        9000000006456888 9000000006456880 900000010039f950 0000000000000001
        0000000000000001 cb0cb028ec7e52e1 0000000002b90000 9000000100348700
        0000000000000000 0000000000000001 ffffffff916d12f1 0000000000000003
        0000000000040000 9000000007930370 0000000002b90000 0000000000000004
        9000000006366000 900000000619a140 0000000000000000 0000000000000004
        0000000000000000 0000000000000009 ffffffffffc681f2 9000000002123940
        9000000001ca55f8 9000000006366000 90000000047a4828 00007ffff057ded8
        00000000000000b0 0000000000000000 0000000000000000 0000000000071000
        ...
Call Trace:
[<90000000047a4828>] show_stack+0x48/0x1a0
[<9000000005b61874>] dump_stack_lvl+0x84/0xcc
[<90000000047f60ac>] __warn+0x8c/0x1e0
[<9000000005b0ab34>] report_bug+0x1b4/0x280
[<9000000005b63110>] do_bp+0x2d0/0x480
[<90000000047a2e20>] handle_bp+0x120/0x1c0
[<90000000048e3334>] rcu_cpu_starting+0x214/0x280
[<90000000047bd568>] tlb_init+0x248/0x528
[<90000000047a4c44>] per_cpu_trap_init+0x124/0x160
[<90000000047a19f4>] cpu_probe+0x494/0xa00
[<90000000047b551c>] start_secondary+0x3c/0xc0
[<9000000005b66134>] smpboot_entry+0x50/0x58

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:26:31 +01:00
Masahiro Yamada
c0b07b4237 LoongArch: Select HAVE_ARCH_SECCOMP to use the common SECCOMP menu
[ Upstream commit 6b79ecd084c99b31c8b4d0beda08893716d5558e ]

LoongArch missed the refactoring made by commit 282a181b1a0d ("seccomp:
Move config option SECCOMP to arch/Kconfig") because LoongArch was not
mainlined at that time.

The 'depends on PROC_FS' statement is stale as described in that commit.
Select HAVE_ARCH_SECCOMP, and remove the duplicated config entry.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:30 +01:00
Masahiro Yamada
c920f604e0 LoongArch: Select ARCH_ENABLE_THP_MIGRATION instead of redefining it
[ Upstream commit b3ff2d9c3a9c64cd0a011cdd407ffc38a6ea8788 ]

ARCH_ENABLE_THP_MIGRATION is supposed to be selected by arch Kconfig.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:26:30 +01:00
Huacai Chen
9e584ea101 LoongArch/smp: Call rcutree_report_cpu_starting() at tlb_init()
commit 5056c596c3d1848021a4eaa76ee42f4c05c50346 upstream.

Machines which have more than 8 nodes fail to boot SMP after commit
a2ccf46333d7b2cf96 ("LoongArch/smp: Call rcutree_report_cpu_starting()
earlier"). Because such machines use tlb-based per-cpu base address
rather than dmw-based per-cpu base address, resulting per-cpu variables
can only be accessed after tlb_init(). But rcutree_report_cpu_starting()
is now called before tlb_init() and accesses per-cpu variables indeed.

Since the original patch want to avoid the lockdep warning caused by
page allocation in tlb_init(), we can move rcutree_report_cpu_starting()
to tlb_init() where after tlb exception configuration but before page
allocation.

Fixes: a2ccf46333d7b2cf96 ("LoongArch/smp: Call rcutree_report_cpu_starting() earlier")
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-05 20:13:02 +00:00
Huacai Chen
1d15da5601 LoongArch/smp: Call rcutree_report_cpu_starting() earlier
commit a2ccf46333d7b2cf9658f0d82ac74097c1542fae upstream.

rcutree_report_cpu_starting() must be called before cpu_probe() to avoid
the following lockdep splat that triggered by calling __alloc_pages() when
CONFIG_PROVE_RCU_LIST=y:

 =============================
 WARNING: suspicious RCU usage
 6.6.0+ #980 Not tainted
 -----------------------------
 kernel/locking/lockdep.c:3761 RCU-list traversed in non-reader section!!
 other info that might help us debug this:
 RCU used illegally from offline CPU!
 rcu_scheduler_active = 1, debug_locks = 1
 1 lock held by swapper/1/0:
  #0: 900000000c82ef98 (&pcp->lock){+.+.}-{2:2}, at: get_page_from_freelist+0x894/0x1790
 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.6.0+ #980
 Stack : 0000000000000001 9000000004f79508 9000000004893670 9000000100310000
         90000001003137d0 0000000000000000 90000001003137d8 9000000004f79508
         0000000000000000 0000000000000001 0000000000000000 90000000048a3384
         203a656d616e2065 ca43677b3687e616 90000001002c3480 0000000000000008
         000000000000009d 0000000000000000 0000000000000001 80000000ffffe0b8
         000000000000000d 0000000000000033 0000000007ec0000 13bbf50562dad831
         9000000005140748 0000000000000000 9000000004f79508 0000000000000004
         0000000000000000 9000000005140748 90000001002bad40 0000000000000000
         90000001002ba400 0000000000000000 9000000003573ec8 0000000000000000
         00000000000000b0 0000000000000004 0000000000000000 0000000000070000
         ...
 Call Trace:
 [<9000000003573ec8>] show_stack+0x38/0x150
 [<9000000004893670>] dump_stack_lvl+0x74/0xa8
 [<900000000360d2bc>] lockdep_rcu_suspicious+0x14c/0x190
 [<900000000361235c>] __lock_acquire+0xd0c/0x2740
 [<90000000036146f4>] lock_acquire+0x104/0x2c0
 [<90000000048a955c>] _raw_spin_lock_irqsave+0x5c/0x90
 [<900000000381cd5c>] rmqueue_bulk+0x6c/0x950
 [<900000000381fc0c>] get_page_from_freelist+0xd4c/0x1790
 [<9000000003821c6c>] __alloc_pages+0x1bc/0x3e0
 [<9000000003583b40>] tlb_init+0x150/0x2a0
 [<90000000035742a0>] per_cpu_trap_init+0xf0/0x110
 [<90000000035712fc>] cpu_probe+0x3dc/0x7a0
 [<900000000357ed20>] start_secondary+0x40/0xb0
 [<9000000004897138>] smpboot_entry+0x54/0x58

raw_smp_processor_id() is required in order to avoid calling into lockdep
before RCU has declared the CPU to be watched for readers.

See also commit 29368e093921 ("x86/smpboot: Move rcu_cpu_starting() earlier"),
commit de5d9dae150c ("s390/smp: move rcu_cpu_starting() earlier") and commit
99f070b62322 ("powerpc/smp: Call rcu_cpu_starting() earlier").

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-31 16:17:03 -08:00
Hengqi Chen
4631c2dd69 LoongArch: BPF: Prevent out-of-bounds memory access
[ Upstream commit 36a87385e31c9343af9a4756598e704741250a67 ]

The test_tag test triggers an unhandled page fault:

  # ./test_tag
  [  130.640218] CPU 0 Unable to handle kernel paging request at virtual address ffff80001b898004, era == 9000000003137f7c, ra == 9000000003139e70
  [  130.640501] Oops[#3]:
  [  130.640553] CPU: 0 PID: 1326 Comm: test_tag Tainted: G      D    O       6.7.0-rc4-loong-devel-gb62ab1a397cf #47 61985c1d94084daa2432f771daa45b56b10d8d2a
  [  130.640764] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
  [  130.640874] pc 9000000003137f7c ra 9000000003139e70 tp 9000000104cb4000 sp 9000000104cb7a40
  [  130.641001] a0 ffff80001b894000 a1 ffff80001b897ff8 a2 000000006ba210be a3 0000000000000000
  [  130.641128] a4 000000006ba210be a5 00000000000000f1 a6 00000000000000b3 a7 0000000000000000
  [  130.641256] t0 0000000000000000 t1 00000000000007f6 t2 0000000000000000 t3 9000000004091b70
  [  130.641387] t4 000000006ba210be t5 0000000000000004 t6 fffffffffffffff0 t7 90000000040913e0
  [  130.641512] t8 0000000000000005 u0 0000000000000dc0 s9 0000000000000009 s0 9000000104cb7ae0
  [  130.641641] s1 00000000000007f6 s2 0000000000000009 s3 0000000000000095 s4 0000000000000000
  [  130.641771] s5 ffff80001b894000 s6 ffff80001b897fb0 s7 9000000004090c50 s8 0000000000000000
  [  130.641900]    ra: 9000000003139e70 build_body+0x1fcc/0x4988
  [  130.642007]   ERA: 9000000003137f7c build_body+0xd8/0x4988
  [  130.642112]  CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
  [  130.642261]  PRMD: 00000004 (PPLV0 +PIE -PWE)
  [  130.642353]  EUEN: 00000003 (+FPE +SXE -ASXE -BTE)
  [  130.642458]  ECFG: 00071c1c (LIE=2-4,10-12 VS=7)
  [  130.642554] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
  [  130.642658]  BADV: ffff80001b898004
  [  130.642719]  PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
  [  130.642815] Modules linked in: [last unloaded: bpf_testmod(O)]
  [  130.642924] Process test_tag (pid: 1326, threadinfo=00000000f7f4015f, task=000000006499f9fd)
  [  130.643062] Stack : 0000000000000000 9000000003380724 0000000000000000 0000000104cb7be8
  [  130.643213]         0000000000000000 25af8d9b6e600558 9000000106250ea0 9000000104cb7ae0
  [  130.643378]         0000000000000000 0000000000000000 9000000104cb7be8 90000000049f6000
  [  130.643538]         0000000000000090 9000000106250ea0 ffff80001b894000 ffff80001b894000
  [  130.643685]         00007ffffb917790 900000000313ca94 0000000000000000 0000000000000000
  [  130.643831]         ffff80001b894000 0000000000000ff7 0000000000000000 9000000100468000
  [  130.643983]         0000000000000000 0000000000000000 0000000000000040 25af8d9b6e600558
  [  130.644131]         0000000000000bb7 ffff80001b894048 0000000000000000 0000000000000000
  [  130.644276]         9000000104cb7be8 90000000049f6000 0000000000000090 9000000104cb7bdc
  [  130.644423]         ffff80001b894000 0000000000000000 00007ffffb917790 90000000032acfb0
  [  130.644572]         ...
  [  130.644629] Call Trace:
  [  130.644641] [<9000000003137f7c>] build_body+0xd8/0x4988
  [  130.644785] [<900000000313ca94>] bpf_int_jit_compile+0x228/0x4ec
  [  130.644891] [<90000000032acfb0>] bpf_prog_select_runtime+0x158/0x1b0
  [  130.645003] [<90000000032b3504>] bpf_prog_load+0x760/0xb44
  [  130.645089] [<90000000032b6744>] __sys_bpf+0xbb8/0x2588
  [  130.645175] [<90000000032b8388>] sys_bpf+0x20/0x2c
  [  130.645259] [<9000000003f6ab38>] do_syscall+0x7c/0x94
  [  130.645369] [<9000000003121c5c>] handle_syscall+0xbc/0x158
  [  130.645507]
  [  130.645539] Code: 380839f6  380831f9  28412bae <24000ca6> 004081ad  0014cb50  004083e8  02bff34c  58008e91
  [  130.645729]
  [  130.646418] ---[ end trace 0000000000000000 ]---

On my machine, which has CONFIG_PAGE_SIZE_16KB=y, the test failed at
loading a BPF prog with 2039 instructions:

  prog = (struct bpf_prog *)ffff80001b894000
  insn = (struct bpf_insn *)(prog->insnsi)ffff80001b894048
  insn + 2039 = (struct bpf_insn *)ffff80001b898000 <- end of the page

In the build_insn() function, we are trying to access next instruction
unconditionally, i.e. `(insn + 1)->imm`. The address lies in the next
page and can be not owned by the current process, thus an page fault is
inevitable and then segfault.

So, let's access next instruction only under `dst = imm64` context.

With this fix, we have:

  # ./test_tag
  test_tag: OK (40945 tests)

Fixes: bbfddb904df6f82 ("LoongArch: BPF: Avoid declare variables in switch-case")
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:27:50 -08:00
Xi Ruoyao
516ecb2436 LoongArch: Fix and simplify fcsr initialization on execve()
commit c2396651309eba291c15e32db8fbe44c738b5921 upstream.

There has been a lingering bug in LoongArch Linux systems causing some
GCC tests to intermittently fail (see Closes link).  I've made a minimal
reproducer:

    zsh% cat measure.s
    .align 4
    .globl _start
    _start:
        movfcsr2gr  $a0, $fcsr0
        bstrpick.w  $a0, $a0, 16, 16
        beqz        $a0, .ok
        break       0
    .ok:
        li.w        $a7, 93
        syscall     0
    zsh% cc mesaure.s -o measure -nostdlib
    zsh% echo $((1.0/3))
    0.33333333333333331
    zsh% while ./measure; do ; done

This while loop should not stop as POSIX is clear that execve must set
fenv to the default, where FCSR should be zero.  But in fact it will
just stop after running for a while (normally less than 30 seconds).
Note that "$((1.0/3))" is needed to reproduce this issue because it
raises FE_INVALID and makes fcsr0 non-zero.

The problem is we are currently relying on SET_PERSONALITY2() to reset
current->thread.fpu.fcsr.  But SET_PERSONALITY2() is executed before
start_thread which calls lose_fpu(0).  We can see if kernel preempt is
enabled, we may switch to another thread after SET_PERSONALITY2() but
before lose_fpu(0).  Then bad thing happens: during the thread switch
the value of the fcsr0 register is stored into current->thread.fpu.fcsr,
making it dirty again.

The issue can be fixed by setting current->thread.fpu.fcsr after
lose_fpu(0) because lose_fpu() clears TIF_USEDFPU, then the thread
switch won't touch current->thread.fpu.fcsr.

The only other architecture setting FCSR in SET_PERSONALITY2() is MIPS.
I've ran a similar test on MIPS with mainline kernel and it turns out
MIPS is buggy, too.  Anyway MIPS do this for supporting different FP
flavors (NaN encodings, etc.) which do not exist on LoongArch.  So for
LoongArch, we can simply remove the current->thread.fpu.fcsr setting
from SET_PERSONALITY2() and do it in start_thread(), after lose_fpu(0).

The while loop failing with the mainline kernel has survived one hour
after this change on LoongArch.

Fixes: 803b0fc5c3f2baa ("LoongArch: Add process management")
Closes: https://github.com/loongson-community/discussions/issues/7
Link: https://lore.kernel.org/linux-mips/7a6aa1bbdbbe2e63ae96ff163fab0349f58f1b9e.camel@xry111.site/
Cc: stable@vger.kernel.org
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 15:27:43 -08:00
Hengqi Chen
c3597996a3 LoongArch: Preserve syscall nr across execve()
[ Upstream commit d6c5f06e46a836e6a70c7cfd95bb38a67d9252ec ]

Currently, we store syscall nr in pt_regs::regs[11] and syscall execve()
accidentally overrides it during its execution:

    sys_execve()
      -> do_execve()
        -> do_execveat_common()
          -> bprm_execve()
            -> exec_binprm()
              -> search_binary_handler()
                -> load_elf_binary()
                  -> ELF_PLAT_INIT()

ELF_PLAT_INIT() reset regs[11] to 0, so in syscall_exit_to_user_mode()
we later get a wrong syscall nr. This breaks tools like execsnoop since
it relies on execve() tracepoints.

Skip pt_regs::regs[11] reset in ELF_PLAT_INIT() to fix the issue.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-20 11:50:06 +01:00
Bibo Mao
355170a7ec LoongArch: Implement constant timer shutdown interface
[ Upstream commit d43f37b73468c172bc89ac4824a1511b411f0778 ]

When a cpu is hot-unplugged, it is put in idle state and the function
arch_cpu_idle_dead() is called. The timer interrupt for this processor
should be disabled, otherwise there will be pending timer interrupt for
the unplugged cpu, so that vcpu is prevented from giving up scheduling
when system is running in vm mode.

This patch implements the timer shutdown interface so that the constant
timer will be properly disabled when a CPU is hot-unplugged.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-20 17:00:23 +01:00
Masahiro Yamada
adb6a90754 LoongArch: Add dependency between vmlinuz.efi and vmlinux.efi
[ Upstream commit d3ec75bc635cb0cb8185b63293d33a3d1b942d22 ]

A common issue in Makefile is a race in parallel building.

You need to be careful to prevent multiple threads from writing to the
same file simultaneously.

Commit 3939f3345050 ("ARM: 8418/1: add boot image dependencies to not
generate invalid images") addressed such a bad scenario.

A similar symptom occurs with the following command:

  $ make -j$(nproc) ARCH=loongarch vmlinux.efi vmlinuz.efi
    [ snip ]
    SORTTAB vmlinux
    OBJCOPY arch/loongarch/boot/vmlinux.efi
    OBJCOPY arch/loongarch/boot/vmlinux.efi
    PAD     arch/loongarch/boot/vmlinux.bin
    GZIP    arch/loongarch/boot/vmlinuz
    OBJCOPY arch/loongarch/boot/vmlinuz.o
    LD      arch/loongarch/boot/vmlinuz.efi.elf
    OBJCOPY arch/loongarch/boot/vmlinuz.efi

The log "OBJCOPY arch/loongarch/boot/vmlinux.efi" is displayed twice.

It indicates that two threads simultaneously enter arch/loongarch/boot/
and write to arch/loongarch/boot/vmlinux.efi.

It occasionally leads to a build failure:

  $ make -j$(nproc) ARCH=loongarch vmlinux.efi vmlinuz.efi
    [ snip ]
    SORTTAB vmlinux
    OBJCOPY arch/loongarch/boot/vmlinux.efi
    PAD     arch/loongarch/boot/vmlinux.bin
  truncate: Invalid number: ‘arch/loongarch/boot/vmlinux.bin’
  make[2]: *** [drivers/firmware/efi/libstub/Makefile.zboot:13:
  arch/loongarch/boot/vmlinux.bin] Error 1
  make[2]: *** Deleting file 'arch/loongarch/boot/vmlinux.bin'
  make[1]: *** [arch/loongarch/Makefile:146: vmlinuz.efi] Error 2
  make[1]: *** Waiting for unfinished jobs....
  make: *** [Makefile:234: __sub-make] Error 2

vmlinuz.efi depends on vmlinux.efi, but such a dependency is not
specified in arch/loongarch/Makefile.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-20 17:00:23 +01:00
Hengqi Chen
40421e0cf3 LoongArch: BPF: Don't sign extend function return value
[ Upstream commit 5d47ec2e6f4c64e30e392cfe9532df98c9beb106 ]

The `cls_redirect` test triggers a kernel panic like:

  # ./test_progs -t cls_redirect
  Can't find bpf_testmod.ko kernel module: -2
  WARNING! Selftests relying on bpf_testmod.ko will be skipped.
  [   30.938489] CPU 3 Unable to handle kernel paging request at virtual address fffffffffd814de0, era == ffff800002009fb8, ra == ffff800002009f9c
  [   30.939331] Oops[#1]:
  [   30.939513] CPU: 3 PID: 1260 Comm: test_progs Not tainted 6.7.0-rc2-loong-devel-g2f56bb0d2327 #35 a896aca3f4164f09cc346f89f2e09832e07be5f6
  [   30.939732] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
  [   30.939901] pc ffff800002009fb8 ra ffff800002009f9c tp 9000000104da4000 sp 9000000104da7ab0
  [   30.940038] a0 fffffffffd814de0 a1 9000000104da7a68 a2 0000000000000000 a3 9000000104da7c10
  [   30.940183] a4 9000000104da7c14 a5 0000000000000002 a6 0000000000000021 a7 00005555904d7f90
  [   30.940321] t0 0000000000000110 t1 0000000000000000 t2 fffffffffd814de0 t3 0004c4b400000000
  [   30.940456] t4 ffffffffffffffff t5 00000000c3f63600 t6 0000000000000000 t7 0000000000000000
  [   30.940590] t8 000000000006d803 u0 0000000000000020 s9 9000000104da7b10 s0 900000010504c200
  [   30.940727] s1 fffffffffd814de0 s2 900000010504c200 s3 9000000104da7c10 s4 9000000104da7ad0
  [   30.940866] s5 0000000000000000 s6 90000000030e65bc s7 9000000104da7b44 s8 90000000044f6fc0
  [   30.941015]    ra: ffff800002009f9c bpf_prog_846803e5ae81417f_cls_redirect+0xa0/0x590
  [   30.941535]   ERA: ffff800002009fb8 bpf_prog_846803e5ae81417f_cls_redirect+0xbc/0x590
  [   30.941696]  CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
  [   30.942224]  PRMD: 00000004 (PPLV0 +PIE -PWE)
  [   30.942330]  EUEN: 00000003 (+FPE +SXE -ASXE -BTE)
  [   30.942453]  ECFG: 00071c1c (LIE=2-4,10-12 VS=7)
  [   30.942612] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
  [   30.942764]  BADV: fffffffffd814de0
  [   30.942854]  PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
  [   30.942974] Modules linked in:
  [   30.943078] Process test_progs (pid: 1260, threadinfo=00000000ce303226, task=000000007d10bb76)
  [   30.943306] Stack : 900000010a064000 90000000044f6fc0 9000000104da7b48 0000000000000000
  [   30.943495]         0000000000000000 9000000104da7c14 9000000104da7c10 900000010504c200
  [   30.943626]         0000000000000001 ffff80001b88c000 9000000104da7b70 90000000030e6668
  [   30.943785]         0000000000000000 9000000104da7b58 ffff80001b88c048 9000000003d05000
  [   30.943936]         900000000303ac88 0000000000000000 0000000000000000 9000000104da7b70
  [   30.944091]         0000000000000000 0000000000000001 0000000731eeab00 0000000000000000
  [   30.944245]         ffff80001b88c000 0000000000000000 0000000000000000 54b99959429f83b8
  [   30.944402]         ffff80001b88c000 90000000044f6fc0 9000000101d70000 ffff80001b88c000
  [   30.944538]         000000000000005a 900000010504c200 900000010a064000 900000010a067000
  [   30.944697]         9000000104da7d88 0000000000000000 9000000003d05000 90000000030e794c
  [   30.944852]         ...
  [   30.944924] Call Trace:
  [   30.945120] [<ffff800002009fb8>] bpf_prog_846803e5ae81417f_cls_redirect+0xbc/0x590
  [   30.945650] [<90000000030e6668>] bpf_test_run+0x1ec/0x2f8
  [   30.945958] [<90000000030e794c>] bpf_prog_test_run_skb+0x31c/0x684
  [   30.946065] [<90000000026d4f68>] __sys_bpf+0x678/0x2724
  [   30.946159] [<90000000026d7288>] sys_bpf+0x20/0x2c
  [   30.946253] [<90000000032dd224>] do_syscall+0x7c/0x94
  [   30.946343] [<9000000002541c5c>] handle_syscall+0xbc/0x158
  [   30.946492]
  [   30.946549] Code: 0015030e  5c0009c0  5001d000 <28c00304> 02c00484  29c00304  00150009  2a42d2e4  0280200d
  [   30.946793]
  [   30.946971] ---[ end trace 0000000000000000 ]---
  [   32.093225] Kernel panic - not syncing: Fatal exception in interrupt
  [   32.093526] Kernel relocated by 0x2320000
  [   32.093630]  .text @ 0x9000000002520000
  [   32.093725]  .data @ 0x9000000003400000
  [   32.093792]  .bss  @ 0x9000000004413200
  [   34.971998] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

This is because we signed-extend function return values. When subprog
mode is enabled, we have:

  cls_redirect()
    -> get_global_metrics() returns pcpu ptr 0xfffffefffc00b480

The pointer returned is later signed-extended to 0xfffffffffc00b480 at
`BPF_JMP | BPF_EXIT`. During BPF prog run, this triggers unhandled page
fault and a kernel panic.

Drop the unnecessary signed-extension on return values like other
architectures do.

With this change, we have:

  # ./test_progs -t cls_redirect
  Can't find bpf_testmod.ko kernel module: -2
  WARNING! Selftests relying on bpf_testmod.ko will be skipped.
  #51/1    cls_redirect/cls_redirect_inlined:OK
  #51/2    cls_redirect/IPv4 TCP accept unknown (no hops, flags: SYN):OK
  #51/3    cls_redirect/IPv6 TCP accept unknown (no hops, flags: SYN):OK
  #51/4    cls_redirect/IPv4 TCP accept unknown (no hops, flags: ACK):OK
  #51/5    cls_redirect/IPv6 TCP accept unknown (no hops, flags: ACK):OK
  #51/6    cls_redirect/IPv4 TCP forward unknown (one hop, flags: ACK):OK
  #51/7    cls_redirect/IPv6 TCP forward unknown (one hop, flags: ACK):OK
  #51/8    cls_redirect/IPv4 TCP accept known (one hop, flags: ACK):OK
  #51/9    cls_redirect/IPv6 TCP accept known (one hop, flags: ACK):OK
  #51/10   cls_redirect/IPv4 UDP accept unknown (no hops, flags: none):OK
  #51/11   cls_redirect/IPv6 UDP accept unknown (no hops, flags: none):OK
  #51/12   cls_redirect/IPv4 UDP forward unknown (one hop, flags: none):OK
  #51/13   cls_redirect/IPv6 UDP forward unknown (one hop, flags: none):OK
  #51/14   cls_redirect/IPv4 UDP accept known (one hop, flags: none):OK
  #51/15   cls_redirect/IPv6 UDP accept known (one hop, flags: none):OK
  #51/16   cls_redirect/cls_redirect_subprogs:OK
  #51/17   cls_redirect/IPv4 TCP accept unknown (no hops, flags: SYN):OK
  #51/18   cls_redirect/IPv6 TCP accept unknown (no hops, flags: SYN):OK
  #51/19   cls_redirect/IPv4 TCP accept unknown (no hops, flags: ACK):OK
  #51/20   cls_redirect/IPv6 TCP accept unknown (no hops, flags: ACK):OK
  #51/21   cls_redirect/IPv4 TCP forward unknown (one hop, flags: ACK):OK
  #51/22   cls_redirect/IPv6 TCP forward unknown (one hop, flags: ACK):OK
  #51/23   cls_redirect/IPv4 TCP accept known (one hop, flags: ACK):OK
  #51/24   cls_redirect/IPv6 TCP accept known (one hop, flags: ACK):OK
  #51/25   cls_redirect/IPv4 UDP accept unknown (no hops, flags: none):OK
  #51/26   cls_redirect/IPv6 UDP accept unknown (no hops, flags: none):OK
  #51/27   cls_redirect/IPv4 UDP forward unknown (one hop, flags: none):OK
  #51/28   cls_redirect/IPv6 UDP forward unknown (one hop, flags: none):OK
  #51/29   cls_redirect/IPv4 UDP accept known (one hop, flags: none):OK
  #51/30   cls_redirect/IPv6 UDP accept known (one hop, flags: none):OK
  #51/31   cls_redirect/cls_redirect_dynptr:OK
  #51/32   cls_redirect/IPv4 TCP accept unknown (no hops, flags: SYN):OK
  #51/33   cls_redirect/IPv6 TCP accept unknown (no hops, flags: SYN):OK
  #51/34   cls_redirect/IPv4 TCP accept unknown (no hops, flags: ACK):OK
  #51/35   cls_redirect/IPv6 TCP accept unknown (no hops, flags: ACK):OK
  #51/36   cls_redirect/IPv4 TCP forward unknown (one hop, flags: ACK):OK
  #51/37   cls_redirect/IPv6 TCP forward unknown (one hop, flags: ACK):OK
  #51/38   cls_redirect/IPv4 TCP accept known (one hop, flags: ACK):OK
  #51/39   cls_redirect/IPv6 TCP accept known (one hop, flags: ACK):OK
  #51/40   cls_redirect/IPv4 UDP accept unknown (no hops, flags: none):OK
  #51/41   cls_redirect/IPv6 UDP accept unknown (no hops, flags: none):OK
  #51/42   cls_redirect/IPv4 UDP forward unknown (one hop, flags: none):OK
  #51/43   cls_redirect/IPv6 UDP forward unknown (one hop, flags: none):OK
  #51/44   cls_redirect/IPv4 UDP accept known (one hop, flags: none):OK
  #51/45   cls_redirect/IPv6 UDP accept known (one hop, flags: none):OK
  #51      cls_redirect:OK
  Summary: 1/45 PASSED, 0 SKIPPED, 0 FAILED

Fixes: 5dc615520c4d ("LoongArch: Add BPF JIT support")
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:39:23 +01:00
Hengqi Chen
ebb09d58df LoongArch: BPF: Don't sign extend memory load operand
[ Upstream commit fe5757553bf9ebe45ae8ecab5922f6937c8d8dfc ]

The `cgrp_local_storage` test triggers a kernel panic like:

  # ./test_progs -t cgrp_local_storage
  Can't find bpf_testmod.ko kernel module: -2
  WARNING! Selftests relying on bpf_testmod.ko will be skipped.
  [  550.930632] CPU 1 Unable to handle kernel paging request at virtual address 0000000000000080, era == ffff80000200be34, ra == ffff80000200be00
  [  550.931781] Oops[#1]:
  [  550.931966] CPU: 1 PID: 1303 Comm: test_progs Not tainted 6.7.0-rc2-loong-devel-g2f56bb0d2327 #35 a896aca3f4164f09cc346f89f2e09832e07be5f6
  [  550.932215] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
  [  550.932403] pc ffff80000200be34 ra ffff80000200be00 tp 9000000108350000 sp 9000000108353dc0
  [  550.932545] a0 0000000000000000 a1 0000000000000517 a2 0000000000000118 a3 00007ffffbb15558
  [  550.932682] a4 00007ffffbb15620 a5 90000001004e7700 a6 0000000000000021 a7 0000000000000118
  [  550.932824] t0 ffff80000200bdc0 t1 0000000000000517 t2 0000000000000517 t3 00007ffff1c06ee0
  [  550.932961] t4 0000555578ae04d0 t5 fffffffffffffff8 t6 0000000000000004 t7 0000000000000020
  [  550.933097] t8 0000000000000040 u0 00000000000007b8 s9 9000000108353e00 s0 90000001004e7700
  [  550.933241] s1 9000000004005000 s2 0000000000000001 s3 0000000000000000 s4 0000555555eb2ec8
  [  550.933379] s5 00007ffffbb15bb8 s6 00007ffff1dafd60 s7 000055555663f610 s8 00007ffff1db0050
  [  550.933520]    ra: ffff80000200be00 bpf_prog_98f1b9e767be2a84_on_enter+0x40/0x200
  [  550.933911]   ERA: ffff80000200be34 bpf_prog_98f1b9e767be2a84_on_enter+0x74/0x200
  [  550.934105]  CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
  [  550.934596]  PRMD: 00000004 (PPLV0 +PIE -PWE)
  [  550.934712]  EUEN: 00000003 (+FPE +SXE -ASXE -BTE)
  [  550.934836]  ECFG: 00071c1c (LIE=2-4,10-12 VS=7)
  [  550.934976] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
  [  550.935097]  BADV: 0000000000000080
  [  550.935181]  PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
  [  550.935291] Modules linked in:
  [  550.935391] Process test_progs (pid: 1303, threadinfo=000000006c3b1c41, task=0000000061f84a55)
  [  550.935643] Stack : 00007ffffbb15bb8 0000555555eb2ec8 0000000000000000 0000000000000001
  [  550.935844]         9000000004005000 ffff80001b864000 00007ffffbb15450 90000000029aa034
  [  550.935990]         0000000000000000 9000000108353ec0 0000000000000118 d07d9dfb09721a09
  [  550.936175]         0000000000000001 0000000000000000 9000000108353ec0 0000000000000118
  [  550.936314]         9000000101d46ad0 900000000290abf0 000055555663f610 0000000000000000
  [  550.936479]         0000000000000003 9000000108353ec0 00007ffffbb15450 90000000029d7288
  [  550.936635]         00007ffff1dafd60 000055555663f610 0000000000000000 0000000000000003
  [  550.936779]         9000000108353ec0 90000000035dd1f0 00007ffff1dafd58 9000000002841c5c
  [  550.936939]         0000000000000119 0000555555eea5a8 00007ffff1d78780 00007ffffbb153e0
  [  550.937083]         ffffffffffffffda 00007ffffbb15518 0000000000000040 00007ffffbb15558
  [  550.937224]         ...
  [  550.937299] Call Trace:
  [  550.937521] [<ffff80000200be34>] bpf_prog_98f1b9e767be2a84_on_enter+0x74/0x200
  [  550.937910] [<90000000029aa034>] bpf_trace_run2+0x90/0x154
  [  550.938105] [<900000000290abf0>] syscall_trace_enter.isra.0+0x1cc/0x200
  [  550.938224] [<90000000035dd1f0>] do_syscall+0x48/0x94
  [  550.938319] [<9000000002841c5c>] handle_syscall+0xbc/0x158
  [  550.938477]
  [  550.938607] Code: 580009ae  50016000  262402e4 <28c20085> 14092084  03a00084  16000024  03240084  00150006
  [  550.938851]
  [  550.939021] ---[ end trace 0000000000000000 ]---

Further investigation shows that this panic is triggered by memory
load operations:

  ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0,
                             BPF_LOCAL_STORAGE_GET_F_CREATE);

The expression `task->cgroups->dfl_cgrp` involves two memory load.
Since the field offset fits in imm12 or imm14, we use ldd or ldptrd
instructions. But both instructions have the side effect that it will
signed-extended the imm operand. Finally, we got the wrong addresses
and panics is inevitable.

Use a generic ldxd instruction to avoid this kind of issues.

With this change, we have:

  # ./test_progs -t cgrp_local_storage
  Can't find bpf_testmod.ko kernel module: -2
  WARNING! Selftests relying on bpf_testmod.ko will be skipped.
  test_cgrp_local_storage:PASS:join_cgroup /cgrp_local_storage 0 nsec
  #48/1    cgrp_local_storage/tp_btf:OK
  test_attach_cgroup:PASS:skel_open 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  libbpf: prog 'update_cookie_tracing': failed to attach: ERROR: strerror_r(-524)=22
  test_attach_cgroup:FAIL:prog_attach unexpected error: -524
  #48/2    cgrp_local_storage/attach_cgroup:FAIL
  test_recursion:PASS:skel_open_and_load 0 nsec
  libbpf: prog 'on_lookup': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'on_lookup': failed to auto-attach: -524
  test_recursion:FAIL:skel_attach unexpected error: -524 (errno 524)
  #48/3    cgrp_local_storage/recursion:FAIL
  #48/4    cgrp_local_storage/negative:OK
  #48/5    cgrp_local_storage/cgroup_iter_sleepable:OK
  test_yes_rcu_lock:PASS:skel_open 0 nsec
  test_yes_rcu_lock:PASS:skel_load 0 nsec
  libbpf: prog 'yes_rcu_lock': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'yes_rcu_lock': failed to auto-attach: -524
  test_yes_rcu_lock:FAIL:skel_attach unexpected error: -524 (errno 524)
  #48/6    cgrp_local_storage/yes_rcu_lock:FAIL
  #48/7    cgrp_local_storage/no_rcu_lock:OK
  #48      cgrp_local_storage:FAIL

  All error logs:
  test_cgrp_local_storage:PASS:join_cgroup /cgrp_local_storage 0 nsec
  test_attach_cgroup:PASS:skel_open 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  test_attach_cgroup:PASS:prog_attach 0 nsec
  libbpf: prog 'update_cookie_tracing': failed to attach: ERROR: strerror_r(-524)=22
  test_attach_cgroup:FAIL:prog_attach unexpected error: -524
  #48/2    cgrp_local_storage/attach_cgroup:FAIL
  test_recursion:PASS:skel_open_and_load 0 nsec
  libbpf: prog 'on_lookup': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'on_lookup': failed to auto-attach: -524
  test_recursion:FAIL:skel_attach unexpected error: -524 (errno 524)
  #48/3    cgrp_local_storage/recursion:FAIL
  test_yes_rcu_lock:PASS:skel_open 0 nsec
  test_yes_rcu_lock:PASS:skel_load 0 nsec
  libbpf: prog 'yes_rcu_lock': failed to attach: ERROR: strerror_r(-524)=22
  libbpf: prog 'yes_rcu_lock': failed to auto-attach: -524
  test_yes_rcu_lock:FAIL:skel_attach unexpected error: -524 (errno 524)
  #48/6    cgrp_local_storage/yes_rcu_lock:FAIL
  #48      cgrp_local_storage:FAIL
  Summary: 0/4 PASSED, 0 SKIPPED, 1 FAILED

No panics any more (The test still failed because lack of BPF trampoline
which I am actively working on).

Fixes: 5dc615520c4d ("LoongArch: Add BPF JIT support")
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:39:23 +01:00
Nathan Chancellor
9f74b261e4 LoongArch: Mark __percpu functions as always inline
commit 71945968d8b128c955204baa33ec03bdd91bdc26 upstream.

A recent change to the optimization pipeline in LLVM reveals some
fragility around the inlining of LoongArch's __percpu functions, which
manifests as a BUILD_BUG() failure:

  In file included from kernel/sched/build_policy.c:17:
  In file included from include/linux/sched/cputime.h:5:
  In file included from include/linux/sched/signal.h:5:
  In file included from include/linux/rculist.h:11:
  In file included from include/linux/rcupdate.h:26:
  In file included from include/linux/irqflags.h:18:
  arch/loongarch/include/asm/percpu.h:97:3: error: call to '__compiletime_assert_51' declared with 'error' attribute: BUILD_BUG failed
     97 |                 BUILD_BUG();
        |                 ^
  include/linux/build_bug.h:59:21: note: expanded from macro 'BUILD_BUG'
     59 | #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
        |                     ^
  include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG'
     39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
        |                                     ^
  include/linux/compiler_types.h:425:2: note: expanded from macro 'compiletime_assert'
    425 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
        |         ^
  include/linux/compiler_types.h:413:2: note: expanded from macro '_compiletime_assert'
    413 |         __compiletime_assert(condition, msg, prefix, suffix)
        |         ^
  include/linux/compiler_types.h:406:4: note: expanded from macro '__compiletime_assert'
    406 |                         prefix ## suffix();                             \
        |                         ^
  <scratch space>:86:1: note: expanded from here
     86 | __compiletime_assert_51
        | ^
  1 error generated.

If these functions are not inlined (which the compiler is free to do
even with functions marked with the standard 'inline' keyword), the
BUILD_BUG() in the default case cannot be eliminated since the compiler
cannot prove it is never used, resulting in a build failure due to the
error attribute.

Mark these functions as __always_inline to guarantee inlining so that
the BUILD_BUG() only triggers when the default case genuinely cannot be
eliminated due to an unexpected size.

Cc:  <stable@vger.kernel.org>
Closes: https://github.com/ClangBuiltLinux/linux/issues/1955
Fixes: 46859ac8af52 ("LoongArch: Add multi-processor (SMP) support")
Link: 1a2e77cf9e
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:07:19 +00:00
Huacai Chen
ec80ad4585 LoongArch: Replace kmap_atomic() with kmap_local_page() in copy_user_highpage()
[ Upstream commit 477a0ebec101359f49d92796e3b609857d564b52 ]

Replace kmap_atomic()/kunmap_atomic() calls with kmap_local_page()/
kunmap_local() in copy_user_highpage() which can be invoked from both
preemptible and atomic context [1].

[1] https://lore.kernel.org/all/20201029222652.302358281@linutronix.de/

Suggested-by: Deepak R Varma <drv@mailo.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08 14:11:01 +01:00
Huacai Chen
afe80b58ee LoongArch: Export symbol invalid_pud_table for modules building
[ Upstream commit 449c2756c2323c9e32b2a2fa9c8b59ce91b5819d ]

Export symbol invalid_pud_table for modules building (such as the KVM
module) if 4-level page tables enabled. Otherwise we get:

ERROR: modpost: "invalid_pud_table" [arch/loongarch/kvm/kvm.ko] undefined!

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08 14:11:01 +01:00
Huacai Chen
490f3b805e LoongArch: numa: Fix high_memory calculation
commit 1943feecf80e73ecc03ce40271f29c6cea142bac upstream.

For 64bit kernel without HIGHMEM, high_memory is the virtual address of
the highest physical address in the system. But __va(get_num_physpages()
<< PAGE_SHIFT) is not what we want for high_memory because there may be
holes in the physical address space. On the other hand, max_low_pfn is
calculated from memblock_end_of_DRAM(), which is exactly corresponding
to the highest physical address, so use it for high_memory calculation.

Cc: <stable@vger.kernel.org>
Fixes: d4b6f1562a3c3284adce ("LoongArch: Add Non-Uniform Memory Access (NUMA) support")
Signed-off-by: Chong Qiao <qiaochong@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-06 14:57:01 +02:00
Tiezhu Yang
7bc8585aa0 LoongArch: Define relocation types for ABI v2.10
commit 2761498876adebff77a43574639005b29e912c43 upstream.

The relocation types from 101 to 109 are used by GNU binutils >= 2.41,
add their definitions to use them in later patches.

Link: https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=include/elf/loongarch.h#l230
Cc: <stable@vger.kernel.org>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-06 14:57:01 +02:00
Huacai Chen
f105e893a8 LoongArch: Set all reserved memblocks on Node#0 at initialization
[ Upstream commit b795fb9f5861ee256070d59e33130980a01fadd7 ]

After commit 61167ad5fecdea ("mm: pass nid to reserve_bootmem_region()")
we get a panic if DEFERRED_STRUCT_PAGE_INIT is enabled:

[    0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000000000002b82, era == 90000000040e3f28, ra == 90000000040e3f18
[    0.000000] Oops[#1]:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.5.0+ #733
[    0.000000] pc 90000000040e3f28 ra 90000000040e3f18 tp 90000000046f4000 sp 90000000046f7c90
[    0.000000] a0 0000000000000001 a1 0000000000200000 a2 0000000000000040 a3 90000000046f7ca0
[    0.000000] a4 90000000046f7ca4 a5 0000000000000000 a6 90000000046f7c38 a7 0000000000000000
[    0.000000] t0 0000000000000002 t1 9000000004b00ac8 t2 90000000040e3f18 t3 90000000040f0800
[    0.000000] t4 00000000000f0000 t5 80000000ffffe07e t6 0000000000000003 t7 900000047fff5e20
[    0.000000] t8 aaaaaaaaaaaaaaab u0 0000000000000018 s9 0000000000000000 s0 fffffefffe000000
[    0.000000] s1 0000000000000000 s2 0000000000000080 s3 0000000000000040 s4 0000000000000000
[    0.000000] s5 0000000000000000 s6 fffffefffe000000 s7 900000000470b740 s8 9000000004ad4000
[    0.000000]    ra: 90000000040e3f18 reserve_bootmem_region+0xec/0x21c
[    0.000000]   ERA: 90000000040e3f28 reserve_bootmem_region+0xfc/0x21c
[    0.000000]  CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
[    0.000000]  PRMD: 00000000 (PPLV0 -PIE -PWE)
[    0.000000]  EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
[    0.000000]  ECFG: 00070800 (LIE=11 VS=7)
[    0.000000] ESTAT: 00010800 [PIL] (IS=11 ECode=1 EsubCode=0)
[    0.000000]  BADV: 0000000000002b82
[    0.000000]  PRID: 0014d000 (Loongson-64bit, Loongson-3A6000)
[    0.000000] Modules linked in:
[    0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____))
[    0.000000] Stack : 0000000000000000 9000000002eb5430 0000003a00000020 90000000045ccd00
[    0.000000]         900000000470e000 90000000002c1918 0000000000000000 9000000004110780
[    0.000000]         00000000fe6c0000 0000000480000000 9000000004b4e368 9000000004110748
[    0.000000]         0000000000000000 900000000421ca84 9000000004620000 9000000004564970
[    0.000000]         90000000046f7d78 9000000002cc9f70 90000000002c1918 900000000470e000
[    0.000000]         9000000004564970 90000000040bc0e0 90000000046f7d78 0000000000000000
[    0.000000]         0000000000004000 90000000045ccd00 0000000000000000 90000000002c1918
[    0.000000]         90000000002c1900 900000000470b700 9000000004b4df78 9000000004620000
[    0.000000]         90000000046200a8 90000000046200a8 0000000000000000 9000000004218b2c
[    0.000000]         9000000004270008 0000000000000001 0000000000000000 90000000045ccd00
[    0.000000]         ...
[    0.000000] Call Trace:
[    0.000000] [<90000000040e3f28>] reserve_bootmem_region+0xfc/0x21c
[    0.000000] [<900000000421ca84>] memblock_free_all+0x114/0x350
[    0.000000] [<9000000004218b2c>] mm_core_init+0x138/0x3cc
[    0.000000] [<9000000004200e38>] start_kernel+0x488/0x7a4
[    0.000000] [<90000000040df0d8>] kernel_entry+0xd8/0xdc
[    0.000000]
[    0.000000] Code: 02eb21ad  00410f4c  380c31ac <262b818d> 6800b70d  02c1c196  0015001c  57fe4bb1  260002cd

The reason is early memblock_reserve() in memblock_init() set node id to
MAX_NUMNODES, making NODE_DATA(nid) a NULL dereference in the call chain
reserve_bootmem_region() -> init_reserved_page(). After memblock_init(),
those late calls of memblock_reserve() operate on subregions of memblock
.memory regions. As a result, these reserved regions will be set to the
correct node at the first iteration of memmap_init_reserved_pages().

So set all reserved memblocks on Node#0 at initialization can avoid this
panic.

Reported-by: WANG Xuerui <git@xen0n.name>
Tested-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: WANG Xuerui <git@xen0n.name>  # with nits addressed
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-06 14:56:58 +02:00
Hongchen Zhang
cc9bf2d62f LoongArch: mm: Add p?d_leaf() definitions
commit 303be4b33562a5b689261ced1616bf16ad49efa7 upstream.

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 501b81046701
("mips: mm: add p?d_leaf() definitions") add p?d_leaf() definition for
LoongArch.

Fixes: 09cfefb7fa70 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:43:01 +02:00
Qi Hu
ab5c5c10d0 LoongArch: Fix the write_fcsr() macro
[ Upstream commit 346dc929623cef70ff7832a4fa0ffd1b696e312a ]

The "write_fcsr()" macro uses wrong the positions for val and dest in
asm. Fix it!

Reported-by: Miao HAO <haomiao19@mails.ucas.ac.cn>
Signed-off-by: Qi Hu <huqi@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:42:25 +02:00
Hongchen Zhang
9920a52362 LoongArch: Let pmd_present() return true when splitting pmd
[ Upstream commit ddc1729b07cc84bb29f577698b8d2e74a4004a6e ]

When we split a pmd into ptes, pmd_present() and pmd_trans_huge() should
return true, otherwise it would be treated as a swap pmd.

This is the same as arm64 does in commit b65399f6111b ("arm64/mm: Change
THP helpers to comply with generic MM semantics"), we also add a new bit
named _PAGE_PRESENT_INVALID for LoongArch.

Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:42:25 +02:00
Greg Kroah-Hartman
ed2f8701fb Revert "loongarch/cpu: Switch to arch_cpu_finalize_init()"
This reverts commit 08e86d42e2c916e362d124e3bc6c824eb1862498 which is
commit 9841c423164787feb8f1442f922b7d80a70c82f1 upstream.

As Gunter reports:
	Building loongarch:defconfig ... failed
	--------------
	Error log:
	<stdin>:569:2: warning: #warning syscall fstat not implemented [-Wcpp]
	arch/loongarch/kernel/setup.c: In function 'arch_cpu_finalize_init':
	arch/loongarch/kernel/setup.c:86:9: error: implicit declaration of function 'alternative_instructions'

	Actually introduced in v6.1.44 with commit 08e86d42e2c9 ("loongarch/cpu:
	Switch to arch_cpu_finalize_init()"). Alternative instruction support
	was only introduced for loongarch in v6.2 with commit 19e5eb15b00c
	("LoongArch: Add alternative runtime patching mechanism").

So revert it from 6.1.y.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/fcd7b764-9047-22ba-a040-41b6ff99959c@roeck-us.net
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:27:20 +02:00
Thomas Gleixner
08e86d42e2 loongarch/cpu: Switch to arch_cpu_finalize_init()
commit 9841c423164787feb8f1442f922b7d80a70c82f1 upstream

check_bugs() is about to be phased out. Switch over to the new
arch_cpu_finalize_init() implementation.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230613224545.195288218@linutronix.de
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-08 20:03:46 +02:00
Chenguang Zhao
2b58bd3847 LoongArch: BPF: Enable bpf_probe_read{, str}() on LoongArch
commit de0e30bee86d0f99c696a1fea34474e556a946ec upstream.

Currently nettrace does not work on LoongArch due to missing
bpf_probe_read{,str}() support, with the error message:

     ERROR: failed to load kprobe-based eBPF
     ERROR: failed to load kprobe-based bpf

According to commit 0ebeea8ca8a4d1d ("bpf: Restrict bpf_probe_read{,
str}() only to archs where they work"), we only need to select
CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE to add said support,
because LoongArch does have non-overlapping address ranges for kernel
and userspace.

Cc: stable@vger.kernel.org # 6.1
Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 10:24:16 +02:00
Tiezhu Yang
8a5e0c1f71 LoongArch: BPF: Fix check condition to call lu32id in move_imm()
commit 4eece7e6de94d833c8aeed2f438faf487cbf94ff upstream.

As the code comment says, the initial aim is to reduce one instruction
in some corner cases, if bit[51:31] is all 0 or all 1, no need to call
lu32id. That is to say, it should call lu32id only if bit[51:31] is not
all 0 and not all 1. The current code always call lu32id, the result is
right but the logic is unexpected and wrong, fix it.

Cc: stable@vger.kernel.org # 6.1
Fixes: 5dc615520c4d ("LoongArch: Add BPF JIT support")
Reported-by: Colin King (gmail) <colin.i.king@gmail.com>
Closes: https://lore.kernel.org/all/bcf97046-e336-712a-ac68-7fd194f2953e@gmail.com/
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 10:24:15 +02:00
Linus Torvalds
21ee33d51b mm/fault: convert remaining simple cases to lock_mm_and_find_vma()
commit a050ba1e7422f2cc60ff8bfde3f96d34d00cb585 upstream.

This does the simple pattern conversion of alpha, arc, csky, hexagon,
loongarch, nios2, sh, sparc32, and xtensa to the lock_mm_and_find_vma()
helper.  They all have the regular fault handling pattern without odd
special cases.

The remaining architectures all have something that keeps us from a
straightforward conversion: ia64 and parisc have stacks that can grow
both up as well as down (and ia64 has special address region checks).

And m68k, microblaze, openrisc, sparc64, and um end up having extra
rules about only expanding the stack down a limited amount below the
user space stack pointer.  That is something that x86 used to do too
(long long ago), and it probably could just be skipped, but it still
makes the conversion less than trivial.

Note that this conversion was done manually and with the exception of
alpha without any build testing, because I have a fairly limited cross-
building environment.  The cases are all simple, and I went through the
changes several times, but...

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Samuel Mendoza-Jonas <samjonas@amazon.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-01 13:16:25 +02:00
Huacai Chen
cffaa97ffb LoongArch: Fix perf event id calculation
commit 962369120d750cbc9c4dc492f32b4304669ff6aa upstream.

LoongArch PMCFG has 10bit event id rather than 8 bit, so fix it.

Cc: stable@vger.kernel.org
Signed-off-by: Jun Yi <yijun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-21 16:00:54 +02:00
Huacai Chen
be100a8460 LoongArch: Mark 3 symbol exports as non-GPL
commit dce5ea1d0f45fa612f5760b88614a3f32bc75e3f upstream.

vm_map_base, empty_zero_page and invalid_pmd_table could be accessed
widely by some out-of-tree non-GPL but important file systems or drivers
(e.g. OpenZFS). Let's use EXPORT_SYMBOL() instead of EXPORT_SYMBOL_GPL()
to export them, so as to avoid build errors.

1, Details about vm_map_base:

This is a LoongArch-specific symbol and may be referenced through macros
PCI_IOBASE, VMALLOC_START and VMALLOC_END.

2, Details about empty_zero_page:

As it stands today, only 3 architectures export empty_zero_page as a GPL
symbol: IA64, LoongArch and MIPS. LoongArch gets the GPL export by
inheriting from MIPS, and the MIPS export was first introduced in commit
497d2adcbf50b ("[MIPS] Export empty_zero_page for sake of the ext4
module."). The IA64 export was similar: commit a7d57ecf4216e ("[IA64]
Export three symbols for module use") did so for kvm.

In both IA64 and MIPS, the export of empty_zero_page was done for
satisfying some in-kernel component built as module (kvm and ext4
respectively), and given its reasonably low-level nature, GPL is a
reasonable choice. But looking at the bigger picture it is evident most
other architectures do not regard it as GPL, so in effect the symbol
probably should not be treated as such, in favor of consistency.

3, Details about invalid_pmd_table:

Keep consistency with invalid_pte_table and make it be possible by some
modules.

Cc: stable@vger.kernel.org
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-26 14:28:38 +02:00
Huacai Chen
e82caab689 LoongArch: Fix probing of the CRC32 feature
commit df830336045db1246d3245d3737fee9939c5f731 upstream.

Not all LoongArch processors support CRC32 instructions. This feature
is indicated by CPUCFG1.CRC32 (Bit25) but it is wrongly defined in the
previous versions of the ISA manual (and so does in loongarch.h). The
CRC32 feature is set unconditionally now, so fix it.

BTW, expose the CRC32 feature in /proc/cpuinfo.

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-26 14:28:38 +02:00
George Guo
37b39345b9 LoongArch, bpf: Fix jit to skip speculation barrier opcode
[ Upstream commit a6f6a95f25803500079513780d11a911ce551d76 ]

Just skip the opcode(BPF_ST | BPF_NOSPEC) in the BPF JIT instead of
failing to JIT the entire program, given LoongArch currently has no
couterpart of a speculation barrier instruction. To verify the issue,
use the ltp testcase as shown below.

Also, Wang says:

  I can confirm there's currently no speculation barrier equivalent
  on LonogArch. (Loongson says there are builtin mitigations for
  Spectre-V1 and V2 on their chips, and AFAIK efforts to port the
  exploits to mips/LoongArch have all failed a few years ago.)

Without this patch:

  $ ./bpf_prog02
  [...]
  bpf_common.c:123: TBROK: Failed verification: ??? (524)
  [...]
  Summary:
  passed   0
  failed   0
  broken   1
  skipped  0
  warnings 0

With this patch:

  $ ./bpf_prog02
  [...]
  Summary:
  passed   0
  failed   0
  broken   0
  skipped  0
  warnings 0

Fixes: 5dc615520c4d ("LoongArch: Add BPF JIT support")
Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: WANG Xuerui <git@xen0n.name>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/bpf/20230328071335.2664966-1-guodongtai@kylinos.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-20 12:35:08 +02:00
Tiezhu Yang
b9c379e1d7 LoongArch: Only call get_timer_irq() once in constant_clockevent_init()
[ Upstream commit bb7a78e343468873bf00b2b181fcfd3c02d8cb56 ]

Under CONFIG_DEBUG_ATOMIC_SLEEP=y and CONFIG_DEBUG_PREEMPT=y, we can see
the following messages on LoongArch, this is because using might_sleep()
in preemption disable context.

[    0.001127] smp: Bringing up secondary CPUs ...
[    0.001222] Booting CPU#1...
[    0.001244] 64-bit Loongson Processor probed (LA464 Core)
[    0.001247] CPU1 revision is: 0014c012 (Loongson-64bit)
[    0.001250] FPU1 revision is: 00000000
[    0.001252] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283
[    0.001255] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
[    0.001257] preempt_count: 1, expected: 0
[    0.001258] RCU nest depth: 0, expected: 0
[    0.001259] Preemption disabled at:
[    0.001261] [<9000000000223800>] arch_dup_task_struct+0x20/0x110
[    0.001272] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.2.0-rc7+ #43
[    0.001275] Hardware name: Loongson Loongson-3A5000-7A1000-1w-A2101/Loongson-LS3A5000-7A1000-1w-A2101, BIOS vUDK2018-LoongArch-V4.0.05132-beta10 12/13/202
[    0.001277] Stack : 0072617764726148 0000000000000000 9000000000222f1c 90000001001e0000
[    0.001286]         90000001001e3be0 90000001001e3be8 0000000000000000 0000000000000000
[    0.001292]         90000001001e3be8 0000000000000040 90000001001e3cb8 90000001001e3a50
[    0.001297]         9000000001642000 90000001001e3be8 be694d10ce4139dd 9000000100174500
[    0.001303]         0000000000000001 0000000000000001 00000000ffffe0a2 0000000000000020
[    0.001309]         000000000000002f 9000000001354116 00000000056b0000 ffffffffffffffff
[    0.001314]         0000000000000000 0000000000000000 90000000014f6e90 9000000001642000
[    0.001320]         900000000022b69c 0000000000000001 0000000000000000 9000000001736a90
[    0.001325]         9000000100038000 0000000000000000 9000000000222f34 0000000000000000
[    0.001331]         00000000000000b0 0000000000000004 0000000000000000 0000000000070000
[    0.001337]         ...
[    0.001339] Call Trace:
[    0.001342] [<9000000000222f34>] show_stack+0x5c/0x180
[    0.001346] [<90000000010bdd80>] dump_stack_lvl+0x60/0x88
[    0.001352] [<9000000000266418>] __might_resched+0x180/0x1cc
[    0.001356] [<90000000010c742c>] mutex_lock+0x20/0x64
[    0.001359] [<90000000002a8ccc>] irq_find_matching_fwspec+0x48/0x124
[    0.001364] [<90000000002259c4>] constant_clockevent_init+0x68/0x204
[    0.001368] [<900000000022acf4>] start_secondary+0x40/0xa8
[    0.001371] [<90000000010c0124>] smpboot_entry+0x60/0x64

Here are the complete call chains:

smpboot_entry()
  start_secondary()
    constant_clockevent_init()
      get_timer_irq()
        irq_find_matching_fwnode()
          irq_find_matching_fwspec()
            mutex_lock()
              might_sleep()
                __might_sleep()
                  __might_resched()

In order to avoid the above issue, we should break the call chains,
using timer_irq_installed variable as check condition to only call
get_timer_irq() once in constant_clockevent_init() is a simple and
proper way.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22 13:33:54 +01:00
Hengqi Chen
30651cff1e LoongArch, bpf: Use 4 instructions for function address in JIT
[ Upstream commit 64f50f6575721ef03d001e907455cbe3baa2a5b1 ]

This patch fixes the following issue of function calls in JIT, like:

  [   29.346981] multi-func JIT bug 105 != 103

The issus can be reproduced by running the "inline simple bpf_loop call"
verifier test.

This is because we are emiting 2-4 instructions for 64-bit immediate moves.
During the first pass of JIT, the placeholder address is zero, emiting two
instructions for it. In the extra pass, the function address is in XKVRANGE,
emiting four instructions for it. This change the instruction index in
JIT context. Let's always use 4 instructions for function address in JIT.
So that the instruction sequences don't change between the first pass and
the extra pass for function calls.

Fixes: 5dc615520c4d ("LoongArch: Add BPF JIT support")
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/bpf/20230214152633.2265699-1-hengqi.chen@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10 09:33:06 +01:00
Jinyang He
efc1058831 LoongArch: Get frame info in unwind_start() when regs is not available
[ Upstream commit 429a9671f235c94fc4b5d6687308714b74adc820 ]

At unwind_start(), it is better to get its frame info here rather than
get them outside, even we don't have 'regs'. In this way we can simply
use unwind_{start, next_frame, done} outside.

Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-06 08:06:32 +01:00
Huacai Chen
87615c0e53 LoongArch: Add HWCAP_LOONGARCH_CPUCFG to elf_hwcap
commit d52fec86a465355b379e839fa372ead0334d62e6 upstream.

HWCAP_LOONGARCH_CPUCFG is missing in elf_hwcap, so add it for glibc's
later use.

Cc: stable@vger.kernel.org
Reported-by: Yinyu Cai <caiyinyu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-24 07:24:33 +01:00
Huacai Chen
b681604eda LoongArch: mm: Fix huge page entry update for virtual machine
In virtual machine (guest mode), the tlbwr instruction can not write the
last entry of MTLB, so we need to make it non-present by invtlb and then
write it by tlbfill. This also simplify the whole logic.

Signed-off-by: Rui Wang <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-12-08 14:59:15 +08:00
Bibo Mao
143d64bdbd LoongArch: Export symbol for function smp_send_reschedule()
Function smp_send_reschedule() is standard kernel API, which is defined
in header file include/linux/smp.h. However, on LoongArch it is defined
as an inline function, this is confusing and kernel modules can not use
this function.

Now we define smp_send_reschedule() as a general function, and add a
EXPORT_SYMBOL_GPL on this function, so that kernel modules can use it.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-12-08 14:59:15 +08:00
Linus Torvalds
bdaa78c6aa 15 hotfixes. 11 marked cc:stable. Only three or four of the latter
address post-6.0 issues, which is hopefully a sign that things are
 converging.
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Merge tag 'mm-hotfixes-stable-2022-12-02' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc hotfixes from Andrew Morton:
 "15 hotfixes,  11 marked cc:stable.

  Only three or four of the latter address post-6.0 issues, which is
  hopefully a sign that things are converging"

* tag 'mm-hotfixes-stable-2022-12-02' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  revert "kbuild: fix -Wimplicit-function-declaration in license_is_gpl_compatible"
  Kconfig.debug: provide a little extra FRAME_WARN leeway when KASAN is enabled
  drm/amdgpu: temporarily disable broken Clang builds due to blown stack-frame
  mm/khugepaged: invoke MMU notifiers in shmem/file collapse paths
  mm/khugepaged: fix GUP-fast interaction by sending IPI
  mm/khugepaged: take the right locks for page table retraction
  mm: migrate: fix THP's mapcount on isolation
  mm: introduce arch_has_hw_nonleaf_pmd_young()
  mm: add dummy pmd_young() for architectures not having it
  mm/damon/sysfs: fix wrong empty schemes assumption under online tuning in damon_sysfs_set_schemes()
  tools/vm/slabinfo-gnuplot: use "grep -E" instead of "egrep"
  nilfs2: fix NULL pointer dereference in nilfs_palloc_commit_free_entry()
  hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing
  madvise: use zap_page_range_single for madvise dontneed
  mm: replace VM_WARN_ON to pr_warn if the node is offline with __GFP_THISNODE
2022-12-02 13:39:38 -08:00
Juergen Gross
6617da8fb5 mm: add dummy pmd_young() for architectures not having it
In order to avoid #ifdeffery add a dummy pmd_young() implementation as a
fallback.  This is required for the later patch "mm: introduce
arch_has_hw_nonleaf_pmd_young()".

Link: https://lkml.kernel.org/r/fd3ac3cd-7349-6bbd-890a-71a9454ca0b3@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30 14:49:41 -08:00
KaiLong Wang
b96e74bb43 LoongArch: Fix unsigned comparison with less than zero
Eliminate the following coccicheck warning:

./arch/loongarch/kernel/unwind_prologue.c:84:5-13: WARNING: Unsigned
expression compared with zero: frame_ra < 0

Signed-off-by: KaiLong Wang <wangkailong@jari.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Huacai Chen
54e6cd42a1 LoongArch: Set _PAGE_DIRTY only if _PAGE_MODIFIED is set in {pmd,pte}_mkwrite()
Set _PAGE_DIRTY only if _PAGE_MODIFIED is set in {pmd,pte}_mkwrite().
Otherwise, _PAGE_DIRTY silences the TLB modify exception and make us
have no chance to mark a pmd/pte dirty (_PAGE_MODIFIED) for software.

Reviewed-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Huacai Chen
bf2f34a506 LoongArch: Set _PAGE_DIRTY only if _PAGE_WRITE is set in {pmd,pte}_mkdirty()
Now {pmd,pte}_mkdirty() set _PAGE_DIRTY bit unconditionally, this causes
random segmentation fault after commit 0ccf7f168e17bb7e ("mm/thp: carry
over dirty bit when thp splits on pmd").

The reason is: when fork(), parent process use pmd_wrprotect() to clear
huge page's _PAGE_WRITE and _PAGE_DIRTY (for COW); then pte_mkdirty() set
_PAGE_DIRTY as well as _PAGE_MODIFIED while splitting dirty huge pages;
once _PAGE_DIRTY is set, there will be no tlb modify exception so the COW
machanism fails; and at last memory corruption occurred between parent
and child processes.

So, we should set _PAGE_DIRTY only when _PAGE_WRITE is set in {pmd,pte}_
mkdirty().

Cc: stable@vger.kernel.org
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Huacai Chen
e428e96135 LoongArch: Clear FPU/SIMD thread info flags for kernel thread
If a kernel thread is created by a user thread, it may carry FPU/SIMD
thread info flags (TIF_USEDFPU, TIF_USEDSIMD, etc.). Then it will be
considered as a fpu owner and kernel try to save its FPU/SIMD context
and cause such errors:

[   41.518931] do_fpu invoked from kernel context![#1]:
[   41.523933] CPU: 1 PID: 395 Comm: iou-wrk-394 Not tainted 6.1.0-rc5+ #217
[   41.530757] Hardware name: Loongson Loongson-3A5000-7A1000-1w-CRB/Loongson-LS3A5000-7A1000-1w-CRB, BIOS vUDK2018-LoongArch-V2.0.pre-beta8 08/18/2022
[   41.544064] $ 0   : 0000000000000000 90000000011e9468 9000000106c7c000 9000000106c7fcf0
[   41.552101] $ 4   : 9000000106305d40 9000000106689800 9000000106c7fd08 0000000003995818
[   41.560138] $ 8   : 0000000000000001 90000000009a72e4 0000000000000020 fffffffffffffffc
[   41.568174] $12   : 0000000000000000 0000000000000000 0000000000000020 00000009aab7e130
[   41.576211] $16   : 00000000000001ff 0000000000000407 0000000000000001 0000000000000000
[   41.584247] $20   : 0000000000000000 0000000000000001 9000000106c7fd70 90000001002f0400
[   41.592284] $24   : 0000000000000000 900000000178f740 90000000011e9834 90000001063057c0
[   41.600320] $28   : 0000000000000000 0000000000000001 9000000006826b40 9000000106305140
[   41.608356] era   : 9000000000228848 _save_fp+0x0/0xd8
[   41.613542] ra    : 90000000011e9468 __schedule+0x568/0x8d0
[   41.619160] CSR crmd: 000000b0
[   41.619163] CSR prmd: 00000000
[   41.622359] CSR euen: 00000000
[   41.625558] CSR ecfg: 00071c1c
[   41.628756] CSR estat: 000f0000
[   41.635239] ExcCode : f (SubCode 0)
[   41.638783] PrId  : 0014c010 (Loongson-64bit)
[   41.643191] Modules linked in: acpi_ipmi vfat fat ipmi_si ipmi_devintf cfg80211 ipmi_msghandler rfkill fuse efivarfs
[   41.653734] Process iou-wrk-394 (pid: 395, threadinfo=0000000004ebe913, task=00000000636fa1be)
[   41.662375] Stack : 00000000ffff0875 9000000006800ec0 9000000006800ec0 90000000002d57e0
[   41.670412]         0000000000000001 0000000000000000 9000000106535880 0000000000000001
[   41.678450]         9000000105291800 0000000000000000 9000000105291838 900000000178e000
[   41.686487]         9000000106c7fd90 9000000106305140 0000000000000001 90000000011e9834
[   41.694523]         00000000ffff0875 90000000011f034c 9000000105291838 9000000105291830
[   41.702561]         0000000000000000 9000000006801440 00000000ffff0875 90000000002d48c0
[   41.710597]         9000000128800001 9000000106305140 9000000105291838 9000000105291838
[   41.718634]         9000000105291830 9000000107811740 9000000105291848 90000000009bf1e0
[   41.726672]         9000000105291830 9000000107811748 2d6b72772d756f69 0000000000343933
[   41.734708]         0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   41.742745]         ...
[   41.745252] Call Trace:
[   42.197868] [<9000000000228848>] _save_fp+0x0/0xd8
[   42.205214] [<90000000011ed468>] __schedule+0x568/0x8d0
[   42.210485] [<90000000011ed834>] schedule+0x64/0xd4
[   42.215411] [<90000000011f434c>] schedule_timeout+0x88/0x188
[   42.221115] [<90000000009c36d0>] io_wqe_worker+0x184/0x350
[   42.226645] [<9000000000221cf0>] ret_from_kernel_thread+0xc/0x9c

This can be easily triggered by ltp testcase syscalls/io_uring02 and it
can also be easily fixed by clearing the FPU/SIMD thread info flags for
kernel threads in copy_thread().

Cc: stable@vger.kernel.org
Reported-by: Qi Hu <huqi@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Huacai Chen
c56ab8e85d LoongArch: SMP: Change prefix from loongson3 to loongson
SMP operations can be shared by Loongson-2 series and Loongson-3 series,
so we change the prefix from loongson3 to loongson for all functions and
data structures.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Huacai Chen
538eafc6de LoongArch: Combine acpi_boot_table_init() and acpi_boot_init()
Combine acpi_boot_table_init() and acpi_boot_init() since they are very
simple, and we don't need to check the return value of acpi_boot_init().

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Tiezhu Yang
83f638bca0 LoongArch: Makefile: Use "grep -E" instead of "egrep"
The latest version of grep claims the egrep is now obsolete so the build
now contains warnings that look like:
	egrep: warning: egrep is obsolescent; using grep -E

Fix this up by changing the LoongArch Makefile to use "grep -E" instead.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-11-21 19:02:57 +08:00
Huacai Chen
bbfddb904d LoongArch: BPF: Avoid declare variables in switch-case
Not all compilers support declare variables in switch-case, so move
declarations to the beginning of a function. Otherwise we may get such
build errors:

arch/loongarch/net/bpf_jit.c: In function ‘emit_atomic’:
arch/loongarch/net/bpf_jit.c:362:3: error: a label can only be part of a statement and a declaration is not a statement
   u8 r0 = regmap[BPF_REG_0];
   ^~
arch/loongarch/net/bpf_jit.c: In function ‘build_insn’:
arch/loongarch/net/bpf_jit.c:727:3: error: a label can only be part of a statement and a declaration is not a statement
   u8 t7 = -1;
   ^~
arch/loongarch/net/bpf_jit.c:778:3: error: a label can only be part of a statement and a declaration is not a statement
   int ret;
   ^~~
arch/loongarch/net/bpf_jit.c:779:3: error: expected expression before ‘u64’
   u64 func_addr;
   ^~~
arch/loongarch/net/bpf_jit.c:780:3: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
   bool func_addr_fixed;
   ^~~~
arch/loongarch/net/bpf_jit.c:784:11: error: ‘func_addr’ undeclared (first use in this function); did you mean ‘in_addr’?
          &func_addr, &func_addr_fixed);
           ^~~~~~~~~
           in_addr
arch/loongarch/net/bpf_jit.c:784:11: note: each undeclared identifier is reported only once for each function it appears in
arch/loongarch/net/bpf_jit.c:814:3: error: a label can only be part of a statement and a declaration is not a statement
   u64 imm64 = (u64)(insn + 1)->imm << 32 | (u32)insn->imm;
   ^~~

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29 16:29:31 +08:00