diff options
| -rw-r--r-- | arch/arm/kernel/unwind.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c index e619ec7856b7..a37ea6c772cd 100644 --- a/arch/arm/kernel/unwind.c +++ b/arch/arm/kernel/unwind.c @@ -33,6 +33,8 @@ #include <asm/traps.h> #include <asm/unwind.h> +#include "reboot.h" + /* Dummy functions to avoid linker complaints */ void __aeabi_unwind_cpp_pr0(void) { @@ -52,7 +54,6 @@ EXPORT_SYMBOL(__aeabi_unwind_cpp_pr2); struct unwind_ctrl_block { unsigned long vrs[16]; /* virtual register set */ const unsigned long *insn; /* pointer to the current instructions word */ - unsigned long sp_low; /* lowest value of sp allowed */ unsigned long sp_high; /* highest value of sp allowed */ unsigned long *lr_addr; /* address of LR value on the stack */ /* @@ -262,9 +263,6 @@ static int unwind_exec_pop_subset_r4_to_r13(struct unwind_ctrl_block *ctrl, } if (!load_sp) { ctrl->vrs[SP] = (unsigned long)vsp; - } else { - ctrl->sp_low = ctrl->vrs[SP]; - ctrl->sp_high = ALIGN(ctrl->sp_low, THREAD_SIZE); } return URC_OK; @@ -323,7 +321,6 @@ static int unwind_exec_insn(struct unwind_ctrl_block *ctrl) ctrl->vrs[SP] += ((insn & 0x3f) << 2) + 4; else if ((insn & 0xc0) == 0x40) { ctrl->vrs[SP] -= ((insn & 0x3f) << 2) + 4; - ctrl->sp_low = ctrl->vrs[SP]; } else if ((insn & 0xf0) == 0x80) { unsigned long mask; @@ -341,8 +338,6 @@ static int unwind_exec_insn(struct unwind_ctrl_block *ctrl) } else if ((insn & 0xf0) == 0x90 && (insn & 0x0d) != 0x0d) { ctrl->vrs[SP] = ctrl->vrs[insn & 0x0f]; - ctrl->sp_low = ctrl->vrs[SP]; - ctrl->sp_high = ALIGN(ctrl->sp_low, THREAD_SIZE); } else if ((insn & 0xf0) == 0xa0) { ret = unwind_exec_pop_r4_to_rN(ctrl, insn); if (ret) @@ -388,10 +383,11 @@ int unwind_frame(struct stackframe *frame) { const struct unwind_idx *idx; struct unwind_ctrl_block ctrl; + unsigned long sp_low; /* store the highest address on the stack to avoid crossing it*/ - ctrl.sp_low = frame->sp; - ctrl.sp_high = ALIGN(ctrl.sp_low - THREAD_SIZE, THREAD_ALIGN) + sp_low = frame->sp; + ctrl.sp_high = ALIGN(sp_low - THREAD_SIZE, THREAD_ALIGN) + THREAD_SIZE; pr_debug("%s(pc = %08lx lr = %08lx sp = %08lx)\n", __func__, @@ -452,6 +448,16 @@ int unwind_frame(struct stackframe *frame) ctrl.check_each_pop = 0; + if (prel31_to_addr(&idx->addr_offset) == (u32)&call_with_stack) { + /* + * call_with_stack() is the only place where we permit SP to + * jump from one stack to another, and since we know it is + * guaranteed to happen, set up the SP bounds accordingly. + */ + sp_low = frame->fp; + ctrl.sp_high = ALIGN(frame->fp, THREAD_SIZE); + } + while (ctrl.entries > 0) { int urc; if ((ctrl.sp_high - ctrl.vrs[SP]) < sizeof(ctrl.vrs)) @@ -459,7 +465,7 @@ int unwind_frame(struct stackframe *frame) urc = unwind_exec_insn(&ctrl); if (urc < 0) return urc; - if (ctrl.vrs[SP] < ctrl.sp_low || ctrl.vrs[SP] > ctrl.sp_high) + if (ctrl.vrs[SP] < sp_low || ctrl.vrs[SP] > ctrl.sp_high) return -URC_FAILURE; } |