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| author | Ananth N Mavinakayanahalli <ananth@linux.ibm.com> | 2021-01-25 14:06:43 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-01-30 01:40:04 +0100 |
| commit | 718aae916fa6619c57c348beaedd675835cf1aa1 (patch) | |
| tree | 60a77b05c95e0163382e4f6ac99902156122c1cd /arch/powerpc/lib | |
| parent | powerpc/sstep: Check instruction validity against ISA version before emulation (diff) | |
| download | linux-718aae916fa6619c57c348beaedd675835cf1aa1.tar.xz linux-718aae916fa6619c57c348beaedd675835cf1aa1.zip | |
powerpc/sstep: Fix incorrect return from analyze_instr()
We currently just percolate the return value from analyze_instr()
to the caller of emulate_step(), especially if it is a -1.
For one particular case (opcode = 4) for instructions that aren't
currently emulated, we are returning 'should not be single-stepped'
while we should have returned 0 which says 'did not emulate, may
have to single-step'.
Fixes: 930d6288a26787 ("powerpc: sstep: Add support for maddhd, maddhdu, maddld instructions")
Signed-off-by: Ananth N Mavinakayanahalli <ananth@linux.ibm.com>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161157999039.64773.14950289716779364766.stgit@thinktux.local
Diffstat (limited to 'arch/powerpc/lib')
| -rw-r--r-- | arch/powerpc/lib/sstep.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index f859cbbb6375..e96cff845ef7 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -1445,6 +1445,11 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs, #ifdef __powerpc64__ case 4: + /* + * There are very many instructions with this primary opcode + * introduced in the ISA as early as v2.03. However, the ones + * we currently emulate were all introduced with ISA 3.0 + */ if (!cpu_has_feature(CPU_FTR_ARCH_300)) goto unknown_opcode; @@ -1472,7 +1477,7 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs, * There are other instructions from ISA 3.0 with the same * primary opcode which do not have emulation support yet. */ - return -1; + goto unknown_opcode; #endif case 7: /* mulli */ |