linux/arch/arm/include/asm
Russell King - ARM Linux a4841e39f7 ARM: introduce handle_IRQ() not to dump exception stack
On Mon, Jul 11, 2011 at 3:52 PM, Russell King - ARM Linux
<linux@arm.linux.org.uk> wrote:

...

> The __exception annotation on a function causes this to happen:
>
> [<c002406c>] (asm_do_IRQ+0x6c/0x8c) from [<c0024b84>]
> (__irq_svc+0x44/0xcc)
> Exception stack(0xc3897c78 to 0xc3897cc0)
> 7c60:                                                       4022d320 4022e000
> 7c80: 08000075 00001000 c32273c0 c03ce1c0 c2b49b78 4022d000 c2b420b4 00000001
> 7ca0: 00000000 c3897cfc 00000000 c3897cc0 c00afc54 c002edd8 00000013 ffffffff
>
> Where that stack dump represents the pt_regs for the exception which
> happened.  Any function found in while unwinding will cause this to
> be printed.
>
> If you insert a C function between the IRQ assembly and asm_do_IRQ,
> the
> dump you get from asm_do_IRQ will be the stack for your function,
> not
> the pt_regs.  That makes the feature useless.
>

When __irq_svc - or any of the other exception handling assembly code -
calls the C code, the stack pointer will be pointing at the pt_regs
structure.

All the entry points into C code from the exception handling code are
marked with __exception or __exception_irq_enter to indicate that they
are one of the functions which has pt_regs above them.

Normally, when you've entered asm_do_IRQ() you will have this stack
layout (higher address towards top):

       pt_regs
       asm_do_IRQ frame

If you insert a C function between the exception assembly code and
asm_do_IRQ, you end up with this stack layout instead:

       pt_regs
       your function frame
       asm_do_IRQ frame

This means when we unwind, we'll get to asm_do_IRQ, and rather than
dumping out the pt_regs, we'll dump out your functions stack frame
instead, because that's what is above the asm_do_IRQ stack frame
rather than the expected pt_regs structure.

The fix is to introduce handle_IRQ() for no exception stack dump, so
it can be called with MULTI_IRQ_HANDLER is selected and a C function
is between the assembly code and the actual IRQ handling code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
2011-07-12 19:42:40 +08:00
..
hardware clockevents: ARM sp804: allow clockevent name to be specified 2011-05-23 18:04:53 +01:00
mach Merge branch 'devicetree/arm-next' of git://git.secretlab.ca/git/linux-2.6 into devel-stable 2011-05-25 00:08:17 +01:00
a.out-core.h ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump 2011-03-10 15:16:29 +00:00
a.out.h headers_check fix: arm, a.out.h 2009-02-01 11:01:22 +05:30
asm-offsets.h kbuild: move asm-offsets.h to include/generated 2009-12-12 13:08:14 +01:00
assembler.h ARM: 6959/1: SMP build fix for entry-macro-multi.S 2011-06-17 11:25:03 +01:00
atomic.h ARM: 6212/1: atomic ops: add memory constraints to inline asm 2010-07-09 11:29:35 +01:00
auxvec.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
bitops.h arm: use asm-generic/bitops/le.h 2011-05-26 17:12:38 -07:00
bitsperlong.h asm-generic: introduce asm/bitsperlong.h 2009-06-11 21:02:14 +02:00
bug.h [ARM] 5211/2: fix a couple warnings from BUG() usage 2008-09-01 12:06:27 +01:00
bugs.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
byteorder.h byteorder: make swab.h include asm/swab.h like a regular header 2009-01-14 19:56:50 -08:00
cache.h ARM: implement support for read-mostly sections 2010-12-05 08:39:36 +00:00
cacheflush.h Merge branch 'v6v7' into devel 2011-03-16 23:35:26 +00:00
cachetype.h ARM: 6385/1: setup: detect aliasing I-cache when D-cache is non-aliasing 2010-10-04 20:57:09 +01:00
checksum.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
clkdev.h ARM: 6483/1: arm & sh: factorised duplicated clkdev.c 2010-11-26 10:51:04 +00:00
cpu.h ARM: 5872/1: ARM: include needed linux/cpu.h in asm/cpu.h 2010-01-10 13:03:52 +00:00
cputime.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
cputype.h ARM: 6881/1: cputype.h uses __attribute_const__ which requires including kernel.h 2011-04-16 21:42:59 +01:00
current.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
delay.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
device.h Driver Core: Add platform device arch data V3 2009-07-22 00:28:38 +02:00
div64.h [ARM] 5320/1: fix assembly constraints in implementation of do_div() 2008-10-23 12:53:32 +01:00
dma-mapping.h ARM: DMA: add support for DMA debugging 2011-01-06 22:31:11 +00:00
dma.h ARM: Replace platform definition of ISA_DMA_THRESHOLD/MAX_DMA_ADDRESS 2011-05-12 08:36:49 +01:00
domain.h ARM: 6384/1: Remove the domain switching on ARMv6k/v7 CPUs 2010-11-04 15:44:31 +00:00
ecard.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
elf.h ARM: 6883/1: ptrace: Migrate to regsets framework 2011-05-14 21:36:55 +01:00
emergency-restart.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
entry-macro-multi.S ARM: 6959/1: SMP build fix for entry-macro-multi.S 2011-06-17 11:25:03 +01:00
entry-macro-vic2.S ARM: Add common entry code for system with two VICs 2010-01-15 17:10:14 +09:00
errno.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
fb.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
fcntl.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
fiq.h ARM: 6940/1: fiq: Briefly document driver responsibilities for suspend/resume 2011-05-26 10:31:06 +01:00
fixmap.h [ARM] fixmap support 2009-03-15 21:01:20 -04:00
flat.h flat: fix data sections alignment 2009-05-29 08:40:02 -07:00
floppy.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
fncpy.h ARM: 6640/1: Thumb-2: Symbol manipulation macros for function body copying 2011-01-27 11:48:58 +00:00
fpstate.h Fix common misspellings 2011-03-31 11:26:23 -03:00
ftrace.h ARM: 6319/1: ftrace: add Thumb-2 support to dynamic ftrace 2010-09-02 15:28:43 +01:00
futex.h ARM: 6889/1: futex: add SMP futex support when !CPU_USE_DOMAINS 2011-05-12 10:11:44 +01:00
glue-cache.h Fix common misspellings 2011-03-31 11:26:23 -03:00
glue-df.h ARM: move cache/processor/fault glue to separate include files 2011-02-12 11:52:21 +00:00
glue-pf.h ARM: move cache/processor/fault glue to separate include files 2011-02-12 11:52:21 +00:00
glue-proc.h Merge branch 'v6v7' into devel 2011-03-16 23:35:26 +00:00
glue.h Fix common misspellings 2011-03-31 11:26:23 -03:00
gpio.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
hardirq.h ARM: SMP: collect IPI and local timer IRQs for /proc/stat 2010-12-20 15:08:01 +00:00
highmem.h ARM: 6639/1: allow highmem on SMP platforms without h/w TLB ops broadcast 2011-02-23 17:24:17 +00:00
hw_breakpoint.h ARM: hw_breakpoint: unify single-stepping code for watchpoints and breakpoints 2010-12-06 11:55:57 +00:00
hw_irq.h arm: dove: Use proper irq accessor functions 2011-03-29 14:47:57 +02:00
hwcap.h ARM: 6207/1: Replace CONFIG_HAS_TLS_REG with HWCAP_TLS and check for it on V6 2010-07-09 14:41:35 +01:00
i8253.h clocksource: convert footbridge to generic i8253 clocksource 2011-05-14 10:29:48 +01:00
ide.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
io.h ARM: io: ensure inb/outb() et.al. are properly ordered on ARMv6+ 2011-01-31 10:53:42 +00:00
ioctl.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
ioctls.h ioctl: Use asm-generic/ioctls.h on arm (enables termiox) 2010-10-22 10:19:59 -07:00
ipcbuf.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
irq_regs.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
irq.h ARM: introduce handle_IRQ() not to dump exception stack 2011-07-12 19:42:40 +08:00
irqflags.h Fix IRQ flag handling naming 2010-10-07 14:08:55 +01:00
Kbuild archs: replace unifdef-y with header-y 2010-08-14 22:26:51 +02:00
kdebug.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
kexec.h [ARM] add machine-specific hook to machine_kexec 2011-03-03 16:26:55 -05:00
kgdb.h kgdb,arm: fix register dump 2010-10-29 13:14:40 -05:00
kmap_types.h kdb: core for kgdb back end (2 of 2) 2010-05-20 21:04:21 -05:00
kprobes.h ARM: kprobes: Fix probing of conditionally executed instructions 2011-04-28 23:40:54 -04:00
leds.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
limits.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
linkage.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
local64.h arch: Implement local64_t 2010-06-09 11:12:36 +02:00
local.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
localtimer.h ARM: 6759/1: smp: Select local timers vs broadcast timer support runtime 2011-02-23 17:54:27 +00:00
locks.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
mach-types.h arm: move mach-types to include/generated 2009-12-12 13:08:14 +01:00
mc146818rtc.h [ARM] Convert asm/io.h to linux/io.h 2008-09-06 12:10:45 +01:00
memblock.h ARM: fix memblock breakage 2010-10-27 21:41:39 +01:00
memory.h ARM: use ARM_DMA_ZONE_SIZE to adjust the zone sizes 2011-05-12 08:36:53 +01:00
mman.h arm: add arch_mmap_check(), get rid of sys_arm_mremap() 2009-12-11 06:34:09 -05:00
mmu_context.h ARM: add a vma entry for the user accessible vector page 2010-10-01 22:35:19 -04:00
mmu.h ARM: 6490/1: MM: bugfix: initialize spinlock for init_mm.context 2010-11-23 22:46:12 +00:00
module.h ARM: 6766/1: Thumb-2: Reflect ARM/Thumb-2 configuration in module vermagic 2011-02-26 13:36:06 +00:00
msgbuf.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
mtd-xip.h [ARM] move asm/xip.h's mach/hardware.h include to mach/xip.h 2008-12-14 13:22:51 +00:00
mutex.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
nwflash.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
outercache.h Merge branches 'fixes', 'pgt-next' and 'versatile' into devel 2011-03-20 09:32:12 +00:00
page-nommu.h nommu: Remove the memory_start/end variables from ARM page-nommu.h 2009-07-24 12:35:01 +01:00
page.h ARM: 6913/1: sparsemem: allow pfn_valid to be overridden when using SPARSEMEM 2011-05-26 10:23:24 +01:00
param.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
parport.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
pci.h ARM: 6058/1: Add support for PCI domains 2010-04-22 21:38:11 +01:00
percpu.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
perf_event.h irq_work: Add generic hardirq context callbacks 2010-10-18 19:58:50 +02:00
pgalloc.h ARM: 6757/1: fix tlb.h induced linux/swap.h build failure 2011-02-23 16:19:21 +00:00
pgtable-hwdef.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
pgtable-nommu.h ARM: 5988/1: pgprot_dmacoherent() for non-mmu builds 2010-03-13 10:48:22 +00:00
pgtable.h ARM: pgtable: add pud-level code 2011-02-21 19:24:14 +00:00
pmu.h ARM: perf_event: allow platform-specific interrupt handler 2011-02-17 13:55:45 +01:00
poll.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
posix_types.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
proc-fns.h ARM: pm: add generic CPU suspend/resume support 2011-02-22 17:11:23 +00:00
processor.h Merge branch 'misc' into devel 2011-03-16 23:35:25 +00:00
procinfo.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
prom.h arm/dt: probe for platforms via the device tree 2011-05-23 09:30:20 -06:00
ptrace.h ARM: 6883/1: ptrace: Migrate to regsets framework 2011-05-14 21:36:55 +01:00
resource.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
scatterlist.h asm-generic: remove ARCH_HAS_SG_CHAIN in scatterlist.h 2010-05-27 09:12:54 -07:00
sched_clock.h ARM: sched_clock: allow init_sched_clock() to be called early 2011-01-11 16:23:04 +00:00
seccomp.h ARM: SECCOMP support 2010-10-01 22:32:18 -04:00
sections.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
segment.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
sembuf.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
serial.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
setup.h arm/dt: probe for platforms via the device tree 2011-05-23 09:30:20 -06:00
shmbuf.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
shmparam.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
sigcontext.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
siginfo.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
signal.h asm-generic: rename termios.h, signal.h and mman.h 2009-06-11 21:01:52 +02:00
sizes.h ARM: 6871/1: Use asm-generic/sizes.h 2011-04-16 12:52:18 +01:00
smp_plat.h Merge branches 'at91', 'dcache', 'ftrace', 'hwbpt', 'misc', 'mmci', 's3c', 'st-ux' and 'unwind' into devel 2010-10-18 22:34:25 +01:00
smp_scu.h ARM: pm: add function to set WFI low-power mode for SMP CPUs 2011-02-11 12:29:18 +00:00
smp_twd.h ARM: localtimer: clean up local timer on hot unplug 2010-12-20 15:09:16 +00:00
smp.h ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7 2011-05-26 12:14:32 +01:00
socket.h net: Generalize socket rx gap / receive queue overflow cmsg 2009-10-12 13:26:31 -07:00
sockios.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
sparsemem.h [ARM] mm: enable sparsemem on clps7500 and RiscPC 2008-10-01 17:24:04 +01:00
spinlock_types.h locking: Convert raw_rwlock to arch_rwlock 2009-12-14 23:55:32 +01:00
spinlock.h ARM: 6939/1: fix missing 'cpu_relax()' declaration 2011-05-23 17:19:26 +01:00
stackprotector.h ARM: initial stack protector (-fstack-protector) support 2010-06-14 21:31:00 -04:00
stacktrace.h [ARM] 5382/1: unwind: Reorganise the stacktrace support 2009-02-12 13:21:17 +00:00
stat.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
statfs.h ARM: Use <asm-generic/statfs.h> 2008-09-04 09:46:11 +01:00
string.h [ARM] remove memzero() 2008-11-27 12:37:59 +00:00
swab.h ARM: 5772/1: Use REV and REV16 for byte swapping on ARMv6+ 2009-10-25 15:59:53 +00:00
system.h ARM: 6870/1: The mandatory barrier rmb() must be a dsb() in for device accesses 2011-05-12 10:52:00 +01:00
tcm.h ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3 2009-09-15 22:11:05 +01:00
termbits.h tty: Add EXTPROC support for LINEMODE 2010-08-10 13:47:39 -07:00
termios.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
therm.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
thread_info.h ARM: SECCOMP support 2010-10-01 22:32:18 -04:00
thread_notify.h ARM: 6867/1: Introduce THREAD_NOTIFY_COPY for copy_thread() hooks 2011-04-10 21:13:36 +01:00
timex.h [ARM] Move include/asm-arm/arch-* to arch/arm/*/include/mach 2008-08-07 09:55:48 +01:00
tlb.h arm: mmu_gather rework 2011-05-25 08:39:14 -07:00
tlbflush.h ARM: tlb: move noMMU tlb_flush() to asm/tlb.h 2011-02-21 19:29:28 +00:00
tls.h ARM: v6k: select TLS register code according to V6 variants 2011-02-02 21:23:29 +00:00
topology.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
traps.h ARM: 6668/1: ptrace: remove single-step emulation code 2011-02-23 17:24:22 +00:00
types.h remove dma64_addr_t 2011-03-23 19:47:18 -07:00
uaccess.h ARM: 6384/1: Remove the domain switching on ARMv6k/v7 CPUs 2010-11-04 15:44:31 +00:00
ucontext.h Fix common misspellings 2011-03-31 11:26:23 -03:00
unaligned.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
unified.h Fix "W" macro in arch/arm/include/asm/unified.h 2009-09-18 23:30:11 +01:00
unistd.h Merge branch 'setns' 2011-05-28 10:51:01 -07:00
unwind.h [ARM] 5383/2: unwind: Add core support for ARM stack unwinding 2009-02-19 11:26:24 +00:00
user.h ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump 2011-03-10 15:16:29 +00:00
vfp.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00
vfpmacros.h ARM: 6203/1: Make VFPv3 usable on ARMv6 2010-07-09 14:41:34 +01:00
vga.h [ARM] Convert asm/io.h to linux/io.h 2008-09-06 12:10:45 +01:00
xor.h [ARM] move include/asm-arm to arch/arm/include/asm 2008-08-02 21:32:35 +01:00