While this still does not heal the irq stack corruption I see here with
CONFIG_PREEMPT, it remains a bug that may have triggered severe issues,
though only very infrequently. OK, three I-pipe bugs fixed, but the big
one is still open. Sigh...
The following changes since commit b62b3fcb9ec752c89a5185e7863e15f004c32d42:
Jan Kiszka (1):
x86: Drop redundant ipipe_suspend_domain from cpu_idle
are available in the git repository at:
git://git.kiszka.org/ipipe-2.6 queues/2.6.31-x86
Jan Kiszka (1):
x86: Make stack switch in call_softirq atomic
arch/x86/include/asm/irqflags.h | 2 ++
arch/x86/kernel/entry_64.S | 4 ++++
2 files changed, 6 insertions(+), 0 deletions(-)
------
x86: Make stack switch in call_softirq atomic
The interrupt stack must always be switched with hard IRQs disabled as
I-pipe uses it as well. If not, we risk subtle stack corruptions when
preempting call_softirq at the wrong instruction.
Signed-off-by: Jan Kiszka <[email protected]>
---
arch/x86/include/asm/irqflags.h | 2 ++
arch/x86/kernel/entry_64.S | 4 ++++
2 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 1baceba..da1e655 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -223,12 +223,14 @@ static inline unsigned long __raw_local_irq_save(void)
#define ENABLE_INTERRUPTS(clobbers) sti
#endif /* CONFIG_X86_64 */
#define ENABLE_INTERRUPTS_HW_COND sti
+#define DISABLE_INTERRUPTS_HW_COND cli
#define DISABLE_INTERRUPTS_HW(clobbers) cli
#define ENABLE_INTERRUPTS_HW(clobbers) sti
#else /* !CONFIG_IPIPE */
#define ENABLE_INTERRUPTS(x) sti
#define DISABLE_INTERRUPTS(x) cli
#define ENABLE_INTERRUPTS_HW_COND
+#define DISABLE_INTERRUPTS_HW_COND
#define DISABLE_INTERRUPTS_HW(clobbers) DISABLE_INTERRUPTS(clobbers)
#define ENABLE_INTERRUPTS_HW(clobbers) ENABLE_INTERRUPTS(clobbers)
#endif /* !CONFIG_IPIPE */
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index b876c16..5237029 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1413,14 +1413,18 @@ ENTRY(call_softirq)
CFI_REL_OFFSET rbp,0
mov %rsp,%rbp
CFI_DEF_CFA_REGISTER rbp
+ DISABLE_INTERRUPTS_HW_COND
incl PER_CPU_VAR(irq_count)
cmove PER_CPU_VAR(irq_stack_ptr),%rsp
+ ENABLE_INTERRUPTS_HW_COND
push %rbp # backlink for old unwinder
call __do_softirq
+ DISABLE_INTERRUPTS_HW_COND
leaveq
CFI_DEF_CFA_REGISTER rsp
CFI_ADJUST_CFA_OFFSET -8
decl PER_CPU_VAR(irq_count)
+ ENABLE_INTERRUPTS_HW_COND
ret
CFI_ENDPROC
END(call_softirq)
--
1.6.0.2
_______________________________________________
Adeos-main mailing list
[email protected]
https://mail.gna.org/listinfo/adeos-main
