[PATCH v3 2/2] powerpc32: fix check_io_access()
From: Christophe Leroy <hidden>
Date: 2016-05-17 12:01:47
On processors like the 8xx, the machine check exception can also happen directly on the load/store instruction itself, so that case needs to be handled as well Signed-off-by: Christophe Leroy <redacted> --- arch/powerpc/include/asm/ppc-opcode.h | 1 + arch/powerpc/kernel/traps.c | 13 +++++++++++-- 2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index 37e7b9d..5e613b8 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h@@ -84,6 +84,7 @@ /* opcode and xopcode for instructions */ #define OP_TRAP 3 #define OP_TRAP_64 2 +#define OP_31 31 #define OP_31_XOP_TRAP 4 #define OP_31_XOP_LWZX 23
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 255f5cc..27f1a36 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c@@ -334,6 +334,7 @@ static inline int check_io_access(struct pt_regs *regs) if (((msr & 0xffff0000) == 0 || (msr & (0x80000 | 0x40000))) && (entry = search_exception_tables(regs->nip)) != NULL) { + int op, xop; /* * Check that it's a sync instruction, or somewhere * in the twi; isync; nop sequence that inb/inw/inl uses.
@@ -346,10 +347,18 @@ static inline int check_io_access(struct pt_regs *regs) nip -= 2; else if (*nip == PPC_INST_ISYNC) --nip; - if (*nip == PPC_INST_SYNC || (*nip >> 26) == OP_TRAP) { + if (*nip == PPC_INST_SYNC || (*nip >> 26) == OP_TRAP) + --nip; + op = *nip >> 26; + xop = (*nip >> 1) & 0x3ff; + if (op == OP_LWZ || op == OP_LBZ || op == OP_STW || + op == OP_STB || op == OP_LHZ || op == OP_STH || + (op == OP_31 && + (xop == OP_31_XOP_LBZX || xop == OP_31_XOP_LHBRX || + xop == OP_31_XOP_LWBRX || xop == OP_31_XOP_STBX || + xop == OP_31_XOP_STHBRX || xop == OP_31_XOP_STWBRX))) { unsigned int rb; - --nip; rb = (*nip >> 11) & 0x1f; printk(KERN_DEBUG "%s bad port %lx at %p\n", (*nip & 0x100)? "OUT to": "IN from",
--
2.1.0