From b91e136cdf88e19e998dbf4631ead266de4b80b5 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Thu, 7 Apr 2011 21:56:04 +0000 Subject: powerpc: Use MSR_64BIT in sstep.c, fix kprobes on BOOK3E We check MSR_SF a lot in sstep.c, to decide if we need to emulate the truncation of values when running in 32-bit mode. Factor out that code into a helper, and convert it and the other uses to use MSR_64BIT. This fixes a bug on BOOK3E where kprobes would end up returning to a 32-bit address, because regs->nip was truncated, because (msr & MSR_SF) was false. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/lib/sstep.c | 61 +++++++++++++++++++++--------------------------- 1 file changed, 27 insertions(+), 34 deletions(-) (limited to 'arch/powerpc/lib/sstep.c') diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index ae5189ab0049..0e5e540c7778 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -44,6 +44,18 @@ extern int do_lxvd2x(int rn, unsigned long ea); extern int do_stxvd2x(int rn, unsigned long ea); #endif +/* + * Emulate the truncation of 64 bit values in 32-bit mode. + */ +static unsigned long truncate_if_32bit(unsigned long msr, unsigned long val) +{ +#ifdef __powerpc64__ + if ((msr & MSR_64BIT) == 0) + val &= 0xffffffffUL; +#endif + return val; +} + /* * Determine whether a conditional branch instruction would branch. */ @@ -90,11 +102,8 @@ static unsigned long __kprobes dform_ea(unsigned int instr, struct pt_regs *regs if (instr & 0x04000000) /* update forms */ regs->gpr[ra] = ea; } -#ifdef __powerpc64__ - if (!(regs->msr & MSR_SF)) - ea &= 0xffffffffUL; -#endif - return ea; + + return truncate_if_32bit(regs->msr, ea); } #ifdef __powerpc64__ @@ -113,9 +122,8 @@ static unsigned long __kprobes dsform_ea(unsigned int instr, struct pt_regs *reg if ((instr & 3) == 1) /* update forms */ regs->gpr[ra] = ea; } - if (!(regs->msr & MSR_SF)) - ea &= 0xffffffffUL; - return ea; + + return truncate_if_32bit(regs->msr, ea); } #endif /* __powerpc64 */ @@ -136,11 +144,8 @@ static unsigned long __kprobes xform_ea(unsigned int instr, struct pt_regs *regs if (do_update) /* update forms */ regs->gpr[ra] = ea; } -#ifdef __powerpc64__ - if (!(regs->msr & MSR_SF)) - ea &= 0xffffffffUL; -#endif - return ea; + + return truncate_if_32bit(regs->msr, ea); } /* @@ -466,7 +471,7 @@ static void __kprobes set_cr0(struct pt_regs *regs, int rd) regs->ccr = (regs->ccr & 0x0fffffff) | ((regs->xer >> 3) & 0x10000000); #ifdef __powerpc64__ - if (!(regs->msr & MSR_SF)) + if (!(regs->msr & MSR_64BIT)) val = (int) val; #endif if (val < 0) @@ -487,7 +492,7 @@ static void __kprobes add_with_carry(struct pt_regs *regs, int rd, ++val; regs->gpr[rd] = val; #ifdef __powerpc64__ - if (!(regs->msr & MSR_SF)) { + if (!(regs->msr & MSR_64BIT)) { val = (unsigned int) val; val1 = (unsigned int) val1; } @@ -570,8 +575,7 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr) if ((instr & 2) == 0) imm += regs->nip; regs->nip += 4; - if ((regs->msr & MSR_SF) == 0) - regs->nip &= 0xffffffffUL; + regs->nip = truncate_if_32bit(regs->msr, regs->nip); if (instr & 1) regs->link = regs->nip; if (branch_taken(instr, regs)) @@ -604,13 +608,9 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr) imm -= 0x04000000; if ((instr & 2) == 0) imm += regs->nip; - if (instr & 1) { - regs->link = regs->nip + 4; - if ((regs->msr & MSR_SF) == 0) - regs->link &= 0xffffffffUL; - } - if ((regs->msr & MSR_SF) == 0) - imm &= 0xffffffffUL; + if (instr & 1) + regs->link = truncate_if_32bit(regs->msr, regs->nip + 4); + imm = truncate_if_32bit(regs->msr, imm); regs->nip = imm; return 1; case 19: @@ -618,11 +618,8 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr) case 16: /* bclr */ case 528: /* bcctr */ imm = (instr & 0x400)? regs->ctr: regs->link; - regs->nip += 4; - if ((regs->msr & MSR_SF) == 0) { - regs->nip &= 0xffffffffUL; - imm &= 0xffffffffUL; - } + regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4); + imm = truncate_if_32bit(regs->msr, imm); if (instr & 1) regs->link = regs->nip; if (branch_taken(instr, regs)) @@ -1616,11 +1613,7 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr) return 0; /* invoke DSI if -EFAULT? */ } instr_done: - regs->nip += 4; -#ifdef __powerpc64__ - if ((regs->msr & MSR_SF) == 0) - regs->nip &= 0xffffffffUL; -#endif + regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4); return 1; logical_done: -- cgit v1.2.3 From 268bb0ce3e87872cb9290c322b0d35bce230d88f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 20 May 2011 12:50:29 -0700 Subject: sanitize usage Commit e66eed651fd1 ("list: remove prefetching from regular list iterators") removed the include of prefetch.h from list.h, which uncovered several cases that had apparently relied on that rather obscure header file dependency. So this fixes things up a bit, using grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]') grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]') to guide us in finding files that either need inclusion, or have it despite not needing it. There are more of them around (mostly network drivers), but this gets many core ones. Reported-by: Stephen Rothwell Signed-off-by: Linus Torvalds --- arch/powerpc/lib/sstep.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc/lib/sstep.c') diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index ae5189ab0049..f73daa6f3970 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include -- cgit v1.2.3