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| author | Paul Mundt <lethal@linux-sh.org> | 2007-05-08 15:31:48 +0900 |
|---|---|---|
| committer | Paul Mundt <lethal@hera.kernel.org> | 2007-05-09 01:35:01 +0000 |
| commit | 53f983a90d7908bcece51f86180c7c9b575a1e4d (patch) | |
| tree | da5914e6f18e8dd55563697de7339af2d99d9c18 /arch/sh/kernel/process.c | |
| parent | bd0799977cb9b68aa6a39e9630aeea4778a58385 (diff) | |
| download | linux-53f983a90d7908bcece51f86180c7c9b575a1e4d.tar.gz | |
sh: Fix PC adjustments for varying opcode length.
There are a few different cases for figuring out how to size the instruction. We read in the instruction located at regs->pc - 4 when rewinding the opcode to figure out if there's a 32-bit opcode before the faulting instruction, with a default of a - 2 adjustment on a mismatch. In practice this works for the cases where pc - 4 is just another 16-bit opcode, or we happen to have a 32-bit and a 16-bit immediately preceeding the pc value. In the cases where we aren't rewinding, this is much less ugly.. We also don't bother fixing up the places where we're explicitly dealing with 16-bit instructions, since this might lead to confusion regarding the encoding size possibilities on other CPU variants. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/kernel/process.c')
| -rw-r--r-- | arch/sh/kernel/process.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/sh/kernel/process.c b/arch/sh/kernel/process.c index 209cc9b42186..9005b2f12aaa 100644 --- a/arch/sh/kernel/process.c +++ b/arch/sh/kernel/process.c @@ -498,7 +498,7 @@ asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5, struct pt_regs *regs = RELOC_HIDE(&__regs, 0); /* Rewind */ - regs->pc -= instruction_size(regs->pc); + regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); if (notify_die(DIE_TRAP, regs, regs->tra & 0xff, SIGTRAP) == NOTIFY_STOP) @@ -517,7 +517,7 @@ asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5, struct pt_regs *regs = RELOC_HIDE(&__regs, 0); /* Rewind */ - regs->pc -= instruction_size(regs->pc); + regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); if (notify_die(DIE_TRAP, regs, TRAPA_BUG_OPCODE & 0xff, SIGTRAP) == NOTIFY_STOP) |