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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-03-07 06:48:45 +0100 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-03-09 00:55:08 +0100 |
| commit | a546498f3bf9aac311c66f965186373aee2ca0b0 (patch) | |
| tree | 86fb9a778aba26df3810acd8e52a921a2d84489b /arch/powerpc/kernel/exceptions-64e.S | |
| parent | powerpc: Improve behaviour of irq tracing on 64-bit exception entry (diff) | |
| download | linux-a546498f3bf9aac311c66f965186373aee2ca0b0.tar.xz linux-a546498f3bf9aac311c66f965186373aee2ca0b0.zip | |
powerpc: Call do_page_fault() with interrupts off
We currently turn interrupts back to their previous state before
calling do_page_fault(). This can be annoying when debugging as
a bad fault will potentially have lost some processor state before
getting into the debugger.
We also end up calling some generic code with interrupts enabled
such as notify_page_fault() with interrupts enabled, which could
be unexpected.
This changes our code to behave more like other architectures,
and make the assembly entry code call into do_page_faults() with
interrupts disabled. They are conditionally re-enabled from
within do_page_fault() in the same spot x86 does it.
While there, add the might_sleep() test in the case of a successful
trylock of the mmap semaphore, again like x86.
Also fix a bug in the existing assembly where r12 (_MSR) could get
clobbered by C calls (the DTL accounting in the exception common
macro and DISABLE_INTS) in some cases.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2. Add the r12 clobber fix
Diffstat (limited to 'arch/powerpc/kernel/exceptions-64e.S')
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64e.S | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 429983c06f91..573613d747ac 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -313,7 +313,7 @@ interrupt_end_book3e: NORMAL_EXCEPTION_PROLOG(0x300, PROLOG_ADDITION_2REGS) mfspr r14,SPRN_DEAR mfspr r15,SPRN_ESR - EXCEPTION_COMMON(0x300, PACA_EXGEN, INTS_KEEP) + EXCEPTION_COMMON(0x300, PACA_EXGEN, INTS_DISABLE_ALL) b storage_fault_common /* Instruction Storage Interrupt */ @@ -321,7 +321,7 @@ interrupt_end_book3e: NORMAL_EXCEPTION_PROLOG(0x400, PROLOG_ADDITION_2REGS) li r15,0 mr r14,r10 - EXCEPTION_COMMON(0x400, PACA_EXGEN, INTS_KEEP) + EXCEPTION_COMMON(0x400, PACA_EXGEN, INTS_DISABLE_ALL) b storage_fault_common /* External Input Interrupt */ @@ -591,7 +591,6 @@ storage_fault_common: mr r5,r15 ld r14,PACA_EXGEN+EX_R14(r13) ld r15,PACA_EXGEN+EX_R15(r13) - INTS_RESTORE_HARD bl .do_page_fault cmpdi r3,0 bne- 1f |