From f50ec1f79f9ae8ff85a176d544e21283367f96f5 Mon Sep 17 00:00:00 2001 From: markj Date: Tue, 5 Aug 2014 01:53:15 +0000 Subject: MFC r267759, r267761 r267759: Fix a couple of bugs on amd64 when fetching probe arguments beyond the first five for probes entered through a UD fault (i.e. FBT probes). Specifically, handle the fact that dtrace_invop_callsite must be 16 byte-aligned and thus may not immediately follow the call to dtrace_invop() in dtrace_invop_start(). Also fetch register arguments and the stack pointer through a struct trapframe instead of a struct reg. r267761: Fix some bugs when fetching probe arguments in i386. Firstly ensure that the 4 byte-aligned dtrace_invop_callsite can be found and that it immediately follows the call to dtrace_invop(). Secondly, fix some pointer arithmetic to account for differences between struct i386_frame and illumos' struct frame. Finally, ensure that dtrace_getarg() isn't inlined. It works by following a fixed number of frame pointers to the probe site, so inlining breaks it. PR: 191260 --- sys/cddl/dev/dtrace/i386/dtrace_asm.S | 8 +------- sys/cddl/dev/dtrace/i386/dtrace_isa.c | 7 ++++--- 2 files changed, 5 insertions(+), 10 deletions(-) (limited to 'sys/cddl/dev/dtrace/i386') diff --git a/sys/cddl/dev/dtrace/i386/dtrace_asm.S b/sys/cddl/dev/dtrace/i386/dtrace_asm.S index 1a92818..6338719 100644 --- a/sys/cddl/dev/dtrace/i386/dtrace_asm.S +++ b/sys/cddl/dev/dtrace/i386/dtrace_asm.S @@ -49,14 +49,8 @@ * dtrace_invop wants us to do. */ call dtrace_invop - - /* - * We pushed 3 times for the arguments to dtrace_invop, - * so we need to increment the stack pointer to get rid of - * those values. - */ - addl $12, %esp ALTENTRY(dtrace_invop_callsite) + addl $12, %esp cmpl $DTRACE_INVOP_PUSHL_EBP, %eax je invop_push cmpl $DTRACE_INVOP_POPL_EBP, %eax diff --git a/sys/cddl/dev/dtrace/i386/dtrace_isa.c b/sys/cddl/dev/dtrace/i386/dtrace_isa.c index 3f73a50..21a8154 100644 --- a/sys/cddl/dev/dtrace/i386/dtrace_isa.c +++ b/sys/cddl/dev/dtrace/i386/dtrace_isa.c @@ -413,7 +413,8 @@ dtrace_getarg(int arg, int aframes) for (i = 1; i <= aframes; i++) { fp = fp->f_frame; - if (fp->f_retaddr == (long)dtrace_invop_callsite) { + if (P2ROUNDUP(fp->f_retaddr, 4) == + (long)dtrace_invop_callsite) { /* * If we pass through the invalid op handler, we will * use the pointer that it passed to the stack as the @@ -422,7 +423,7 @@ dtrace_getarg(int arg, int aframes) * beyond the EIP/RIP that was pushed when the trap was * taken -- hence the "+ 1" below. */ - stack = ((uintptr_t **)&fp[1])[1] + 1; + stack = ((uintptr_t **)&fp[1])[0] + 1; goto load; } @@ -438,7 +439,7 @@ dtrace_getarg(int arg, int aframes) */ arg++; - stack = (uintptr_t *)&fp[1]; + stack = (uintptr_t *)fp + 2; load: DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); -- cgit v1.1