diff options
| author | Jinyang He <hejinyang@loongson.cn> | 2023-01-17 11:42:16 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2023-01-17 11:42:16 +0800 |
| commit | dc74a9e8a8c57966a563ab078ba91c8b2c0d0a72 (patch) | |
| tree | bee8ccfdc8c2d89cc9eaf5caeab25771aef92761 /arch/loongarch/kernel/genex.S | |
| parent | c5ac25e0d78a6f63446b8fef4d8630ccd7a2663d (diff) | |
LoongArch: Add generic ex-handler unwind in prologue unwinder
When exception is triggered, code flow go handle_\exception in some
cases. One of stackframe in this case as follows,
high -> +-------+
| REGS | <- a pt_regs
| |
| | <- ex trigger
| REGS | <- ex pt_regs <-+
| | |
| | |
low -> +-------+ ->unwind-+
When unwinder unwinds to handler_\exception it cannot go on prologue
analysis. Because it is an asynchronous code flow, we should get the
next frame PC from regs->csr_era rather than regs->regs[1]. At init time
we copy the handlers to eentry and also copy them to NUMA-affine memory
named pcpu_handlers if NUMA is enabled. Thus, unwinder cannot unwind
normally. To solve this, we try to give some hints in handler_\exception
and fixup unwinders in unwind_next_frame().
Reported-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch/kernel/genex.S')
| -rw-r--r-- | arch/loongarch/kernel/genex.S | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/loongarch/kernel/genex.S b/arch/loongarch/kernel/genex.S index 75e5be807a0d..7e5c293ed89f 100644 --- a/arch/loongarch/kernel/genex.S +++ b/arch/loongarch/kernel/genex.S @@ -67,14 +67,17 @@ SYM_FUNC_END(except_vec_cex) .macro BUILD_HANDLER exception handler prep .align 5 SYM_FUNC_START(handle_\exception) + 666: BACKUP_T0T1 SAVE_ALL build_prep_\prep move a0, sp la.abs t0, do_\handler jirl ra, t0, 0 + 668: RESTORE_ALL_AND_RET SYM_FUNC_END(handle_\exception) + SYM_DATA(unwind_hint_\exception, .word 668b - 666b) .endm BUILD_HANDLER ade ade badv |