From b86432b42eba5671969a9e6483ee219674b7ee25 Mon Sep 17 00:00:00 2001 From: "Zhang, Yanmin" Date: Thu, 16 Nov 2006 01:19:10 -0800 Subject: [PATCH] [PATCH] some irq_chip variables point to NULL I got an oops when booting 2.6.19-rc5-mm1 on my ia64 machine. Below is the log. Oops 11012296146944 [1] Modules linked in: binfmt_misc dm_mirror dm_multipath dm_mod thermal processor f an container button sg eepro100 e100 mii Pid: 0, CPU 0, comm: swapper psr : 0000121008022038 ifs : 800000000000040b ip : [] Not tainted ip is at __do_IRQ+0x371/0x3e0 unat: 0000000000000000 pfs : 000000000000040b rsc : 0000000000000003 rnat: 656960155aa56aa5 bsps: a00000010058b890 pr : 656960155aa55a65 ldrs: 0000000000000000 ccv : 0000000000000000 fpsr: 0009804c0270033f csd : 0000000000000000 ssd : 0000000000000000 b0 : a0000001000e1390 b6 : a0000001005beac0 b7 : e00000007f01aa00 f6 : 000000000000000000000 f7 : 0ffe69090000000000000 f8 : 1000a9090000000000000 f9 : 0ffff8000000000000000 f10 : 1000a908ffffff6f70000 f11 : 1003e0000000000000909 r1 : a000000100fbbff0 r2 : 0000000000010002 r3 : 0000000000010001 r8 : fffffffffffbffff r9 : a000000100bd8060 r10 : a000000100dd83b8 r11 : fffffffffffeffff r12 : a000000100bcbbb0 r13 : a000000100bc4000 r14 : 0000000000010000 r15 : 0000000000010000 r16 : a000000100c01aa8 r17 : a000000100d2c350 r18 : 0000000000000000 r19 : a000000100d2c300 r20 : a000000100c01a88 r21 : 0000000080010100 r22 : a000000100c01ac0 r23 : a0000001000108e0 r24 : e000000477980004 r25 : 0000000000000000 r26 : 0000000000000000 r27 : e00000000913400c r28 : e0000004799ee51c r29 : e0000004778b87f0 r30 : a000000100d2c300 r31 : a00000010005c7e0 Call Trace: [] show_stack+0x40/0xa0 sp=a000000100bcb760 bsp=a000000100bc4f40 [] show_regs+0x840/0x880 sp=a000000100bcb930 bsp=a000000100bc4ee8 [] die+0x250/0x320 sp=a000000100bcb930 bsp=a000000100bc4ea0 [] ia64_do_page_fault+0x8d0/0xa20 sp=a000000100bcb950 bsp=a000000100bc4e50 [] ia64_leave_kernel+0x0/0x290 sp=a000000100bcb9e0 bsp=a000000100bc4e50 [] __do_IRQ+0x370/0x3e0 sp=a000000100bcbbb0 bsp=a000000100bc4df0 [] ia64_handle_irq+0x170/0x220 sp=a000000100bcbbb0 bsp=a000000100bc4dc0 [] ia64_leave_kernel+0x0/0x290 sp=a000000100bcbbb0 bsp=a000000100bc4dc0 [] ia64_pal_call_static+0x90/0xc0 sp=a000000100bcbd80 bsp=a000000100bc4d78 [] default_idle+0x90/0x160 sp=a000000100bcbd80 bsp=a000000100bc4d58 [] cpu_idle+0x1f0/0x440 sp=a000000100bcbe20 bsp=a000000100bc4d18 [] rest_init+0xc0/0xe0 sp=a000000100bcbe20 bsp=a000000100bc4d00 [] start_kernel+0x6a0/0x6c0 sp=a000000100bcbe20 bsp=a000000100bc4ca0 [] __end_ivt_text+0x6d0/0x6f0 sp=a000000100bcbe30 bsp=a000000100bc4c00 <0>Kernel panic - not syncing: Aiee, killing interrupt handler! The root cause is that some irq_chip variables, especially ia64_msi_chip, initiate their memeber end to point to NULL. __do_IRQ doesn't check if irq_chip->end is null and just calls it after processing the interrupt. As irq_chip->end is called at many places, so I fix it by reinitiating irq_chip->end to dummy_irq_chip.end, e.g., a noop function. Signed-off-by: Zhang Yanmin Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/irq/chip.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 2d0dc3efe813..ebfd24a41858 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -233,6 +233,8 @@ void irq_chip_set_defaults(struct irq_chip *chip) chip->shutdown = chip->disable; if (!chip->name) chip->name = chip->typename; + if (!chip->end) + chip->end = dummy_irq_chip.end; } static inline void mask_ack_irq(struct irq_desc *desc, int irq)