diff options
| author | Matt Redfearn <matt.redfearn@imgtec.com> | 2017-08-08 13:22:33 +0100 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2017-09-06 13:20:25 +0200 |
| commit | cea8cd498f4f1c30ea27e3664b3c671e495c4fce (patch) | |
| tree | f16e510564b485a6dffeab795cea7b103b34f7ce /arch/mips/kernel | |
| parent | a0ae2b08331a9882150618e0c81ea837e4a37ace (diff) | |
MIPS: microMIPS: Fix decoding of swsp16 instruction
When the immediate encoded in the instruction is accessed, it is sign
extended due to being a signed value being assigned to a signed integer.
The ISA specifies that this operation is an unsigned operation.
The sign extension leads us to incorrectly decode:
801e9c8e: cbf1 sw ra,68(sp)
As having an immediate of 1073741809.
Since the instruction format does not specify signed/unsigned, and this
is currently the only location to use this instuction format, change it
to an unsigned immediate.
Fixes: bb9bc4689b9c ("MIPS: Calculate microMIPS ra properly when unwinding the stack")
Suggested-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Miodrag Dinic <miodrag.dinic@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16957/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel')
| -rw-r--r-- | arch/mips/kernel/process.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 516089f8c6e7..debc0410a2d5 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -214,7 +214,7 @@ static inline int is_ra_save_ins(union mips_instruction *ip, int *poff) if (ip->mm16_r5_format.rt != 31) return 0; - *poff = ip->mm16_r5_format.simmediate; + *poff = ip->mm16_r5_format.imm; *poff = (*poff << 2) / sizeof(ulong); return 1; |