diff options
| author | Andi Kleen <ak@suse.de> | 2005-07-28 21:15:49 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-07-28 21:46:02 -0700 |
| commit | ed6b676ca8b50e0b538e61c283d52fd04f007abf (patch) | |
| tree | 753ea613ce334c41f835f6aac21074b137d24713 /arch | |
| parent | 3829ee6b1be03d5aa3005fe7d19f30088b539836 (diff) | |
[PATCH] x86_64: Switch to the interrupt stack when running a softirq in local_bh_enable()
This avoids some potential stack overflows with very deep softirq callchains.
i386 does this too.
TOADD CFI annotation
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86_64/kernel/entry.S | 12 | ||||
| -rw-r--r-- | arch/x86_64/kernel/irq.c | 19 |
2 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 0696e025dce..096d470e280 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -918,3 +918,15 @@ ENTRY(machine_check) ENTRY(call_debug) zeroentry do_call_debug +ENTRY(call_softirq) + movq %gs:pda_irqstackptr,%rax + pushq %r15 + movq %rsp,%r15 + incl %gs:pda_irqcount + cmove %rax,%rsp + call __do_softirq + movq %r15,%rsp + decl %gs:pda_irqcount + popq %r15 + ret + diff --git a/arch/x86_64/kernel/irq.c b/arch/x86_64/kernel/irq.c index cc3fb85f514..849a20aec7c 100644 --- a/arch/x86_64/kernel/irq.c +++ b/arch/x86_64/kernel/irq.c @@ -135,3 +135,22 @@ void fixup_irqs(cpumask_t map) local_irq_disable(); } #endif + +extern void call_softirq(void); + +asmlinkage void do_softirq(void) +{ + __u32 pending; + unsigned long flags; + + if (in_interrupt()) + return; + + local_irq_save(flags); + pending = local_softirq_pending(); + /* Switch to interrupt stack */ + if (pending) + call_softirq(); + local_irq_restore(flags); +} +EXPORT_SYMBOL(do_softirq); |