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| author | Kevin Hao <haokexin@gmail.com> | 2014-01-17 04:25:28 (GMT) |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-02-17 00:19:34 (GMT) |
| commit | 1a18a66446f3f289b05b634f18012424d82aa63a (patch) | |
| tree | 290380a5077f36b1039366f7f9b1b0dffd47a72d | |
| parent | cd15b048445d0a54f7147c35a86c5a16ef231554 (diff) | |
| download | linux-1a18a66446f3f289b05b634f18012424d82aa63a.tar.xz | |
powerpc: Set the correct ksp_limit on ppc32 when switching to irq stack
Guenter Roeck has got the following call trace on a p2020 board:
Kernel stack overflow in process eb3e5a00, r1=eb79df90
CPU: 0 PID: 2838 Comm: ssh Not tainted 3.13.0-rc8-juniper-00146-g19eca00 #4
task: eb3e5a00 ti: c0616000 task.ti: ef440000
NIP: c003a420 LR: c003a410 CTR: c0017518
REGS: eb79dee0 TRAP: 0901 Not tainted (3.13.0-rc8-juniper-00146-g19eca00)
MSR: 00029000 <CE,EE,ME> CR: 24008444 XER: 00000000
GPR00: c003a410 eb79df90 eb3e5a00 00000000 eb05d900 00000001 65d87646 00000000
GPR08: 00000000 020b8000 00000000 00000000 44008442
NIP [c003a420] __do_softirq+0x94/0x1ec
LR [c003a410] __do_softirq+0x84/0x1ec
Call Trace:
[eb79df90] [c003a410] __do_softirq+0x84/0x1ec (unreliable)
[eb79dfe0] [c003a970] irq_exit+0xbc/0xc8
[eb79dff0] [c000cc1c] call_do_irq+0x24/0x3c
[ef441f20] [c00046a8] do_IRQ+0x8c/0xf8
[ef441f40] [c000e7f4] ret_from_except+0x0/0x18
--- Exception: 501 at 0xfcda524
LR = 0x10024900
Instruction dump:
7c781b78 3b40000a 3a73b040 543c0024 3a800000 3b3913a0 7ef5bb78 48201bf9
5463103a 7d3b182e 7e89b92e 7c008146 <3ba00000> 7e7e9b78 48000014 57fff87f
Kernel panic - not syncing: kernel stack overflow
CPU: 0 PID: 2838 Comm: ssh Not tainted 3.13.0-rc8-juniper-00146-g19eca00 #4
Call Trace:
The reason is that we have used the wrong register to calculate the
ksp_limit in commit cbc9565ee826 (powerpc: Remove ksp_limit on ppc64).
Just fix it.
As suggested by Benjamin Herrenschmidt, also add the C prototype of the
function in the comment in order to avoid such kind of errors in the
future.
Cc: stable@vger.kernel.org # 3.12
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/kernel/misc_32.S | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S index 879f096..7c6bb4b 100644 --- a/arch/powerpc/kernel/misc_32.S +++ b/arch/powerpc/kernel/misc_32.S @@ -57,11 +57,14 @@ _GLOBAL(call_do_softirq) mtlr r0 blr +/* + * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp); + */ _GLOBAL(call_do_irq) mflr r0 stw r0,4(r1) lwz r10,THREAD+KSP_LIMIT(r2) - addi r11,r3,THREAD_INFO_GAP + addi r11,r4,THREAD_INFO_GAP stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4) mr r1,r4 stw r10,8(r1) |