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| author | Felix Fietkau <nbd@nbd.name> | 2018-04-18 11:21:01 +0200 |
|---|---|---|
| committer | Felix Fietkau <nbd@nbd.name> | 2018-04-18 12:17:28 +0200 |
| commit | ca54bd10057afb732dd65965053b0a00aa0b0640 (patch) | |
| tree | 3e816ef2f25b89d36b564231e2f9b45fe85af324 | |
| parent | bb46520159c0119e829900e29681feea6f297fe0 (diff) | |
| download | upstream-ca54bd10057afb732dd65965053b0a00aa0b0640.tar.gz upstream-ca54bd10057afb732dd65965053b0a00aa0b0640.tar.bz2 upstream-ca54bd10057afb732dd65965053b0a00aa0b0640.zip | |
kernel: fix an issue with infinite stack traces on MIPS
Reproduced by enabling lockdep on MT7621
Signed-off-by: Felix Fietkau <nbd@nbd.name>
| -rw-r--r-- | target/linux/generic/pending-4.14/102-MIPS-only-process-negative-stack-offsets-on-stack-tr.patch | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/target/linux/generic/pending-4.14/102-MIPS-only-process-negative-stack-offsets-on-stack-tr.patch b/target/linux/generic/pending-4.14/102-MIPS-only-process-negative-stack-offsets-on-stack-tr.patch new file mode 100644 index 0000000000..cc17053121 --- /dev/null +++ b/target/linux/generic/pending-4.14/102-MIPS-only-process-negative-stack-offsets-on-stack-tr.patch @@ -0,0 +1,57 @@ +From: Felix Fietkau <nbd@nbd.name> +Date: Wed, 18 Apr 2018 10:50:05 +0200 +Subject: [PATCH] MIPS: only process negative stack offsets on stack traces + +Fixes endless back traces in cases where the compiler emits a stack +pointer increase in a branch delay slot (probably for some form of +function return). + +[ 3.475442] BUG: MAX_STACK_TRACE_ENTRIES too low! +[ 3.480070] turning off the locking correctness validator. +[ 3.485521] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.14.34 #0 +[ 3.491475] Stack : 00000000 00000000 00000000 00000000 80e0fce2 00000034 00000000 00000000 +[ 3.499764] 87c3838c 80696377 8061047c 00000000 00000001 00000001 87c2d850 6534689f +[ 3.508059] 00000000 00000000 80e10000 00000000 00000000 000000cf 0000000f 00000000 +[ 3.516353] 00000000 806a0000 00076891 00000000 00000000 00000000 ffffffff 00000000 +[ 3.524648] 806c0000 00000004 80e10000 806a0000 00000003 80690000 00000000 80700000 +[ 3.532942] ... +[ 3.535362] Call Trace: +[ 3.537818] [<80010a48>] show_stack+0x58/0x100 +[ 3.542207] [<804c2f78>] dump_stack+0xe8/0x170 +[ 3.546613] [<80079f90>] save_trace+0xf0/0x110 +[ 3.551010] [<8007b1ec>] mark_lock+0x33c/0x78c +[ 3.555413] [<8007bf48>] __lock_acquire+0x2ac/0x1a08 +[ 3.560337] [<8007de60>] lock_acquire+0x64/0x8c +[ 3.564846] [<804e1570>] _raw_spin_lock_irqsave+0x54/0x78 +[ 3.570186] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.574770] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.579257] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.583839] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.588329] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.592911] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.597401] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.601983] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.606473] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.611055] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.615545] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.620125] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.624619] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.629197] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.633691] [<801b618c>] kernfs_notify+0x94/0xac +[ 3.638269] [<801b7b10>] sysfs_notify+0x74/0xa0 +[ 3.642763] [<801b618c>] kernfs_notify+0x94/0xac + +Signed-off-by: Felix Fietkau <nbd@nbd.name> +--- + +--- a/arch/mips/kernel/process.c ++++ b/arch/mips/kernel/process.c +@@ -357,6 +357,8 @@ static inline int is_sp_move_ins(union m + + if (ip->i_format.opcode == addiu_op || + ip->i_format.opcode == daddiu_op) { ++ if (ip->i_format.simmediate > 0) ++ return 0; + *frame_size = -ip->i_format.simmediate; + return 1; + } |