* [PATCH] some irq_chip variables initiate end to point to NULL
@ 2006-11-14 9:08 Zhang, Yanmin
2006-11-14 10:05 ` Andrew Morton
0 siblings, 1 reply; 5+ messages in thread
From: Zhang, Yanmin @ 2006-11-14 9:08 UTC (permalink / raw)
To: LKML; +Cc: linux-ia64@vger.kernel.org
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 : [<a0000001000e1411>] 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:
[<a000000100014600>] show_stack+0x40/0xa0
sp=a000000100bcb760 bsp=a000000100bc4f40
[<a000000100014f00>] show_regs+0x840/0x880
sp=a000000100bcb930 bsp=a000000100bc4ee8
[<a000000100037fb0>] die+0x250/0x320
sp=a000000100bcb930 bsp=a000000100bc4ea0
[<a00000010005e5f0>] ia64_do_page_fault+0x8d0/0xa20
sp=a000000100bcb950 bsp=a000000100bc4e50
[<a00000010000caa0>] ia64_leave_kernel+0x0/0x290
sp=a000000100bcb9e0 bsp=a000000100bc4e50
[<a0000001000e1410>] __do_IRQ+0x370/0x3e0
sp=a000000100bcbbb0 bsp=a000000100bc4df0
[<a000000100011f50>] ia64_handle_irq+0x170/0x220
sp=a000000100bcbbb0 bsp=a000000100bc4dc0
[<a00000010000caa0>] ia64_leave_kernel+0x0/0x290
sp=a000000100bcbbb0 bsp=a000000100bc4dc0
[<a000000100012390>] ia64_pal_call_static+0x90/0xc0
sp=a000000100bcbd80 bsp=a000000100bc4d78
[<a000000100015630>] default_idle+0x90/0x160
sp=a000000100bcbd80 bsp=a000000100bc4d58
[<a000000100014290>] cpu_idle+0x1f0/0x440
sp=a000000100bcbe20 bsp=a000000100bc4d18
[<a000000100009980>] rest_init+0xc0/0xe0
sp=a000000100bcbe20 bsp=a000000100bc4d00
[<a0000001009f8ea0>] start_kernel+0x6a0/0x6c0
sp=a000000100bcbe20 bsp=a000000100bc4ca0
[<a0000001000089f0>] __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.
Below patch against 2.6.19-rc5-mm1 fixes it.
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
---
--- linux-2.6.19-rc5-mm1/kernel/irq/chip.c 2006-11-14 14:16:16.000000000 +0800
+++ linux-2.6.19-rc5-mm1_fix/kernel/irq/chip.c 2006-11-14 14:14:25.000000000 +0800
@@ -233,6 +233,8 @@ void irq_chip_set_defaults(struct irq_ch
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)
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] some irq_chip variables initiate end to point to NULL
2006-11-14 9:08 [PATCH] some irq_chip variables initiate end to point to NULL Zhang, Yanmin
@ 2006-11-14 10:05 ` Andrew Morton
2006-11-14 12:46 ` [patch] ia64: use generic_handle_irq() Ingo Molnar
0 siblings, 1 reply; 5+ messages in thread
From: Andrew Morton @ 2006-11-14 10:05 UTC (permalink / raw)
To: Zhang, Yanmin
Cc: LKML, linux-ia64@vger.kernel.org, Ingo Molnar, Thomas Gleixner
On Tue, 14 Nov 2006 17:08:10 +0800
"Zhang, Yanmin" <yanmin_zhang@linux.intel.com> wrote:
> 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 : [<a0000001000e1411>] 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:
> [<a000000100014600>] show_stack+0x40/0xa0
> sp=a000000100bcb760 bsp=a000000100bc4f40
> [<a000000100014f00>] show_regs+0x840/0x880
> sp=a000000100bcb930 bsp=a000000100bc4ee8
> [<a000000100037fb0>] die+0x250/0x320
> sp=a000000100bcb930 bsp=a000000100bc4ea0
> [<a00000010005e5f0>] ia64_do_page_fault+0x8d0/0xa20
> sp=a000000100bcb950 bsp=a000000100bc4e50
> [<a00000010000caa0>] ia64_leave_kernel+0x0/0x290
> sp=a000000100bcb9e0 bsp=a000000100bc4e50
> [<a0000001000e1410>] __do_IRQ+0x370/0x3e0
> sp=a000000100bcbbb0 bsp=a000000100bc4df0
> [<a000000100011f50>] ia64_handle_irq+0x170/0x220
> sp=a000000100bcbbb0 bsp=a000000100bc4dc0
> [<a00000010000caa0>] ia64_leave_kernel+0x0/0x290
> sp=a000000100bcbbb0 bsp=a000000100bc4dc0
> [<a000000100012390>] ia64_pal_call_static+0x90/0xc0
> sp=a000000100bcbd80 bsp=a000000100bc4d78
> [<a000000100015630>] default_idle+0x90/0x160
> sp=a000000100bcbd80 bsp=a000000100bc4d58
> [<a000000100014290>] cpu_idle+0x1f0/0x440
> sp=a000000100bcbe20 bsp=a000000100bc4d18
> [<a000000100009980>] rest_init+0xc0/0xe0
> sp=a000000100bcbe20 bsp=a000000100bc4d00
> [<a0000001009f8ea0>] start_kernel+0x6a0/0x6c0
> sp=a000000100bcbe20 bsp=a000000100bc4ca0
> [<a0000001000089f0>] __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.
>
> Below patch against 2.6.19-rc5-mm1 fixes it.
>
> Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
>
> ---
>
> --- linux-2.6.19-rc5-mm1/kernel/irq/chip.c 2006-11-14 14:16:16.000000000 +0800
> +++ linux-2.6.19-rc5-mm1_fix/kernel/irq/chip.c 2006-11-14 14:14:25.000000000 +0800
> @@ -233,6 +233,8 @@ void irq_chip_set_defaults(struct irq_ch
> chip->shutdown = chip->disable;
> if (!chip->name)
> chip->name = chip->typename;
> + if (!chip->end)
> + chip->end = dummy_irq_chip.end;
> }
>
The same bug should be hitting in mainline, shouldn't it?
^ permalink raw reply [flat|nested] 5+ messages in thread
* [patch] ia64: use generic_handle_irq()
2006-11-14 10:05 ` Andrew Morton
@ 2006-11-14 12:46 ` Ingo Molnar
2006-11-14 18:08 ` Eric W. Biederman
0 siblings, 1 reply; 5+ messages in thread
From: Ingo Molnar @ 2006-11-14 12:46 UTC (permalink / raw)
To: Andrew Morton
Cc: Zhang, Yanmin, LKML, linux-ia64@vger.kernel.org, Thomas Gleixner,
ebiederm
* Andrew Morton <akpm@osdl.org> wrote:
> On Tue, 14 Nov 2006 17:08:10 +0800
> "Zhang, Yanmin" <yanmin_zhang@linux.intel.com> wrote:
>
> > 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 : [<a0000001000e1411>] 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:
> > [<a000000100014600>] show_stack+0x40/0xa0
> > sp=a000000100bcb760 bsp=a000000100bc4f40
> > [<a000000100014f00>] show_regs+0x840/0x880
> > sp=a000000100bcb930 bsp=a000000100bc4ee8
> > [<a000000100037fb0>] die+0x250/0x320
> > sp=a000000100bcb930 bsp=a000000100bc4ea0
> > [<a00000010005e5f0>] ia64_do_page_fault+0x8d0/0xa20
> > sp=a000000100bcb950 bsp=a000000100bc4e50
> > [<a00000010000caa0>] ia64_leave_kernel+0x0/0x290
> > sp=a000000100bcb9e0 bsp=a000000100bc4e50
> > [<a0000001000e1410>] __do_IRQ+0x370/0x3e0
> > sp=a000000100bcbbb0 bsp=a000000100bc4df0
> > [<a000000100011f50>] ia64_handle_irq+0x170/0x220
> > sp=a000000100bcbbb0 bsp=a000000100bc4dc0
> > [<a00000010000caa0>] ia64_leave_kernel+0x0/0x290
> > sp=a000000100bcbbb0 bsp=a000000100bc4dc0
> > [<a000000100012390>] ia64_pal_call_static+0x90/0xc0
> > sp=a000000100bcbd80 bsp=a000000100bc4d78
> > [<a000000100015630>] default_idle+0x90/0x160
> > sp=a000000100bcbd80 bsp=a000000100bc4d58
> > [<a000000100014290>] cpu_idle+0x1f0/0x440
> > sp=a000000100bcbe20 bsp=a000000100bc4d18
> > [<a000000100009980>] rest_init+0xc0/0xe0
> > sp=a000000100bcbe20 bsp=a000000100bc4d00
> > [<a0000001009f8ea0>] start_kernel+0x6a0/0x6c0
> > sp=a000000100bcbe20 bsp=a000000100bc4ca0
> > [<a0000001000089f0>] __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.
> >
> > Below patch against 2.6.19-rc5-mm1 fixes it.
> >
> > Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
> >
> > ---
> >
> > --- linux-2.6.19-rc5-mm1/kernel/irq/chip.c 2006-11-14 14:16:16.000000000 +0800
> > +++ linux-2.6.19-rc5-mm1_fix/kernel/irq/chip.c 2006-11-14 14:14:25.000000000 +0800
> > @@ -233,6 +233,8 @@ void irq_chip_set_defaults(struct irq_ch
> > chip->shutdown = chip->disable;
> > if (!chip->name)
> > chip->name = chip->typename;
> > + if (!chip->end)
> > + chip->end = dummy_irq_chip.end;
> > }
> >
>
> The same bug should be hitting in mainline, shouldn't it?
correct.
this bug comes from a 'mixed' IRQ setup on ia64: half of it is still
old-style, half of it (the MSI stuff) is new-style irqchip code. But the
ia64 lowlevel code unconditionally calls __do_IRQ(), which is a bug.
the genirq code has all the right helpers for such a mixed situation: so
a better fix might be the one below: use generic_handle_irq() instead of
unconditionally calling into __do_IRQ(). But i have not tested it -
Yanmin, can you confirm this too fixes your bug?
similarly, any architecture that makes use of the new generic MSI
infrastructure should not be calling __do_IRQ() directly. (but i'm not
aware of any other besides ia64 - i386 and x86_64 is now fully irq-chip
converted.)
Eric, do you agree?
Ingo
----------------->
From: Ingo Molnar <mingo@elte.hu>
Subject: ia64: use generic_handle_irq()
use generic_handle_irq() to handle mixed-type irq handling.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Index: linux/arch/ia64/kernel/irq.c
===================================================================
--- linux.orig/arch/ia64/kernel/irq.c
+++ linux/arch/ia64/kernel/irq.c
@@ -197,7 +197,7 @@ void fixup_irqs(void)
struct pt_regs *old_regs = set_irq_regs(NULL);
vectors_in_migration[irq]=0;
- __do_IRQ(irq);
+ generic_handle_irq(irq);
set_irq_regs(old_regs);
}
}
Index: linux/arch/ia64/kernel/irq_ia64.c
===================================================================
--- linux.orig/arch/ia64/kernel/irq_ia64.c
+++ linux/arch/ia64/kernel/irq_ia64.c
@@ -186,7 +186,7 @@ ia64_handle_irq (ia64_vector vector, str
ia64_setreg(_IA64_REG_CR_TPR, vector);
ia64_srlz_d();
- __do_IRQ(local_vector_to_irq(vector));
+ generic_handle_irq(local_vector_to_irq(vector));
/*
* Disable interrupts and send EOI:
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [patch] ia64: use generic_handle_irq()
2006-11-14 12:46 ` [patch] ia64: use generic_handle_irq() Ingo Molnar
@ 2006-11-14 18:08 ` Eric W. Biederman
2006-11-15 2:26 ` Zhang, Yanmin
0 siblings, 1 reply; 5+ messages in thread
From: Eric W. Biederman @ 2006-11-14 18:08 UTC (permalink / raw)
To: Ingo Molnar
Cc: Andrew Morton, Zhang, Yanmin, LKML, linux-ia64@vger.kernel.org,
Thomas Gleixner
Ingo Molnar <mingo@elte.hu> writes:
> * Andrew Morton <akpm@osdl.org> wrote:
>
>> On Tue, 14 Nov 2006 17:08:10 +0800
>> "Zhang, Yanmin" <yanmin_zhang@linux.intel.com> wrote:
>>
>> > I got an oops when booting 2.6.19-rc5-mm1 on my ia64 machine.
>> >
>> >
>> > 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.
>> >
>> > Below patch against 2.6.19-rc5-mm1 fixes it.
>> >
>> > Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
>> >
>> > ---
>> >
>> > --- linux-2.6.19-rc5-mm1/kernel/irq/chip.c 2006-11-14 14:16:16.000000000
> +0800
>> > +++ linux-2.6.19-rc5-mm1_fix/kernel/irq/chip.c 2006-11-14 14:14:25.000000000
> +0800
>> > @@ -233,6 +233,8 @@ void irq_chip_set_defaults(struct irq_ch
>> > chip->shutdown = chip->disable;
>> > if (!chip->name)
>> > chip->name = chip->typename;
>> > + if (!chip->end)
>> > + chip->end = dummy_irq_chip.end;
>> > }
>> >
>>
>> The same bug should be hitting in mainline, shouldn't it?
>
> correct.
>
> this bug comes from a 'mixed' IRQ setup on ia64: half of it is still
> old-style, half of it (the MSI stuff) is new-style irqchip code. But the
> ia64 lowlevel code unconditionally calls __do_IRQ(), which is a bug.
Now that we hare half converted yes it is a bug.
> the genirq code has all the right helpers for such a mixed situation: so
> a better fix might be the one below: use generic_handle_irq() instead of
> unconditionally calling into __do_IRQ(). But i have not tested it -
> Yanmin, can you confirm this too fixes your bug?
>
> similarly, any architecture that makes use of the new generic MSI
> infrastructure should not be calling __do_IRQ() directly. (but i'm not
> aware of any other besides ia64 - i386 and x86_64 is now fully irq-chip
> converted.)
>
> Eric, do you agree?
>
This is true in practice. It isn't necessarily true, as all of irq_chip
structures are arch specific. It would be silly to start using msi interrupts
without converting to genirq though. So I think this covers it for ia64.
Your patch only fixes 2 spots and there is a third in irq_ia64.c that
needs to be fixed as well. At least in linus's tree.
>
> Index: linux/arch/ia64/kernel/irq.c
> ===================================================================
> --- linux.orig/arch/ia64/kernel/irq.c
> +++ linux/arch/ia64/kernel/irq.c
> @@ -197,7 +197,7 @@ void fixup_irqs(void)
> struct pt_regs *old_regs = set_irq_regs(NULL);
>
> vectors_in_migration[irq]=0;
> - __do_IRQ(irq);
> + generic_handle_irq(irq);
> set_irq_regs(old_regs);
> }
> }
> Index: linux/arch/ia64/kernel/irq_ia64.c
> ===================================================================
> --- linux.orig/arch/ia64/kernel/irq_ia64.c
> +++ linux/arch/ia64/kernel/irq_ia64.c
> @@ -186,7 +186,7 @@ ia64_handle_irq (ia64_vector vector, str
> ia64_setreg(_IA64_REG_CR_TPR, vector);
> ia64_srlz_d();
>
> - __do_IRQ(local_vector_to_irq(vector));
> + generic_handle_irq(local_vector_to_irq(vector));
>
> /*
> * Disable interrupts and send EOI:
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [patch] ia64: use generic_handle_irq()
2006-11-14 18:08 ` Eric W. Biederman
@ 2006-11-15 2:26 ` Zhang, Yanmin
0 siblings, 0 replies; 5+ messages in thread
From: Zhang, Yanmin @ 2006-11-15 2:26 UTC (permalink / raw)
To: Eric W. Biederman
Cc: Ingo Molnar, Andrew Morton, LKML, linux-ia64@vger.kernel.org,
Thomas Gleixner
On Wed, 2006-11-15 at 02:08, Eric W. Biederman wrote:
> Ingo Molnar <mingo@elte.hu> writes:
>
> > * Andrew Morton <akpm@osdl.org> wrote:
> >
> >> On Tue, 14 Nov 2006 17:08:10 +0800
> >> "Zhang, Yanmin" <yanmin_zhang@linux.intel.com> wrote:
> >>
> >> > I got an oops when booting 2.6.19-rc5-mm1 on my ia64 machine.
> >> >
> >> >
> >> > 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.
> >> >
> >> > Below patch against 2.6.19-rc5-mm1 fixes it.
> >> >
> >> > Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
> >> >
> >> > ---
> >> >
> >> > --- linux-2.6.19-rc5-mm1/kernel/irq/chip.c 2006-11-14 14:16:16.000000000
> > +0800
> >> > +++ linux-2.6.19-rc5-mm1_fix/kernel/irq/chip.c 2006-11-14 14:14:25.000000000
> > +0800
> >> > @@ -233,6 +233,8 @@ void irq_chip_set_defaults(struct irq_ch
> >> > chip->shutdown = chip->disable;
> >> > if (!chip->name)
> >> > chip->name = chip->typename;
> >> > + if (!chip->end)
> >> > + chip->end = dummy_irq_chip.end;
> >> > }
> >> >
> >>
> >> The same bug should be hitting in mainline, shouldn't it?
> >
> > correct.
> >
> > this bug comes from a 'mixed' IRQ setup on ia64: half of it is still
> > old-style, half of it (the MSI stuff) is new-style irqchip code. But the
> > ia64 lowlevel code unconditionally calls __do_IRQ(), which is a bug.
>
> Now that we hare half converted yes it is a bug.
>
> > the genirq code has all the right helpers for such a mixed situation: so
> > a better fix might be the one below: use generic_handle_irq() instead of
> > unconditionally calling into __do_IRQ(). But i have not tested it -
> > Yanmin, can you confirm this too fixes your bug?
> >
> > similarly, any architecture that makes use of the new generic MSI
> > infrastructure should not be calling __do_IRQ() directly. (but i'm not
> > aware of any other besides ia64 - i386 and x86_64 is now fully irq-chip
> > converted.)
> >
> > Eric, do you agree?
> >
>
> This is true in practice. It isn't necessarily true, as all of irq_chip
> structures are arch specific. It would be silly to start using msi interrupts
> without converting to genirq though. So I think this covers it for ia64.
>
> Your patch only fixes 2 spots and there is a third in irq_ia64.c that
> needs to be fixed as well. At least in linus's tree.
Based on Eric's comments, I added a new change into Ingo's patch, and tested
on my ia64 machine. It does fix the bug and works well. I still think
my original patch to initilate null end to dummy_irq_chip.end is useful, at
least to prevent potential errors.
---
--- linux-2.6.19-rc5-mm1/arch/ia64/kernel/irq.c 2006-11-14 14:16:12.000000000 +0800
+++ linux-2.6.19-rc5-mm1_fix/arch/ia64/kernel/irq.c 2006-11-15 09:56:01.000000000 +0800
@@ -197,7 +197,7 @@ void fixup_irqs(void)
struct pt_regs *old_regs = set_irq_regs(NULL);
vectors_in_migration[irq]=0;
- __do_IRQ(irq);
+ generic_handle_irq(irq);
set_irq_regs(old_regs);
}
}
--- linux-2.6.19-rc5-mm1/arch/ia64/kernel/irq_ia64.c 2006-11-14 14:16:12.000000000 +0800
+++ linux-2.6.19-rc5-mm1_fix/arch/ia64/kernel/irq_ia64.c 2006-11-15 09:56:51.000000000 +0800
@@ -186,7 +186,7 @@ ia64_handle_irq (ia64_vector vector, str
ia64_setreg(_IA64_REG_CR_TPR, vector);
ia64_srlz_d();
- __do_IRQ(local_vector_to_irq(vector));
+ generic_handle_irq(local_vector_to_irq(vector));
/*
* Disable interrupts and send EOI:
@@ -242,7 +242,7 @@ void ia64_process_pending_intr(void)
* Probably could shared code.
*/
vectors_in_migration[local_vector_to_irq(vector)]=0;
- __do_IRQ(local_vector_to_irq(vector));
+ generic_handle_irq(local_vector_to_irq(vector));
set_irq_regs(old_regs);
/*
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2006-11-15 2:26 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2006-11-14 9:08 [PATCH] some irq_chip variables initiate end to point to NULL Zhang, Yanmin
2006-11-14 10:05 ` Andrew Morton
2006-11-14 12:46 ` [patch] ia64: use generic_handle_irq() Ingo Molnar
2006-11-14 18:08 ` Eric W. Biederman
2006-11-15 2:26 ` Zhang, Yanmin
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