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author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-10 15:21:55 +0200 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-10 15:21:55 +0200 |
commit | f78a8236c6502760705399dfa42e22ab11aa1e6b (patch) | |
tree | d965f09daff0d531c63e35c764e7061f9c43afe7 /arch/mips/kernel/process.c | |
parent | 6cb3d05f3030deed157c9bbada5c58e7ee0f5172 (diff) | |
parent | 39da7c509acff13fc8cb12ec1bb20337c988ed36 (diff) | |
download | linux-f78a8236c6502760705399dfa42e22ab11aa1e6b.tar.bz2 |
Merge 4.11-rc6 into staging-next
We want the staging and iio fixes in here to handle merging easier.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/mips/kernel/process.c')
-rw-r--r-- | arch/mips/kernel/process.c | 56 |
1 files changed, 38 insertions, 18 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index fb6b6b650719..b68e10fc453d 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -488,31 +488,52 @@ unsigned long notrace unwind_stack_by_address(unsigned long stack_page, unsigned long pc, unsigned long *ra) { + unsigned long low, high, irq_stack_high; struct mips_frame_info info; unsigned long size, ofs; + struct pt_regs *regs; int leaf; - extern void ret_from_irq(void); - extern void ret_from_exception(void); if (!stack_page) return 0; /* - * If we reached the bottom of interrupt context, - * return saved pc in pt_regs. + * IRQ stacks start at IRQ_STACK_START + * task stacks at THREAD_SIZE - 32 */ - if (pc == (unsigned long)ret_from_irq || - pc == (unsigned long)ret_from_exception) { - struct pt_regs *regs; - if (*sp >= stack_page && - *sp + sizeof(*regs) <= stack_page + THREAD_SIZE - 32) { - regs = (struct pt_regs *)*sp; - pc = regs->cp0_epc; - if (!user_mode(regs) && __kernel_text_address(pc)) { - *sp = regs->regs[29]; - *ra = regs->regs[31]; - return pc; - } + low = stack_page; + if (!preemptible() && on_irq_stack(raw_smp_processor_id(), *sp)) { + high = stack_page + IRQ_STACK_START; + irq_stack_high = high; + } else { + high = stack_page + THREAD_SIZE - 32; + irq_stack_high = 0; + } + + /* + * If we reached the top of the interrupt stack, start unwinding + * the interrupted task stack. + */ + if (unlikely(*sp == irq_stack_high)) { + unsigned long task_sp = *(unsigned long *)*sp; + + /* + * Check that the pointer saved in the IRQ stack head points to + * something within the stack of the current task + */ + if (!object_is_on_stack((void *)task_sp)) + return 0; + + /* + * Follow pointer to tasks kernel stack frame where interrupted + * state was saved. + */ + regs = (struct pt_regs *)task_sp; + pc = regs->cp0_epc; + if (!user_mode(regs) && __kernel_text_address(pc)) { + *sp = regs->regs[29]; + *ra = regs->regs[31]; + return pc; } return 0; } @@ -533,8 +554,7 @@ unsigned long notrace unwind_stack_by_address(unsigned long stack_page, if (leaf < 0) return 0; - if (*sp < stack_page || - *sp + info.frame_size > stack_page + THREAD_SIZE - 32) + if (*sp < low || *sp + info.frame_size > high) return 0; if (leaf) |