Messages in this thread Patch in this message | | | Date | Wed, 16 Mar 2022 20:21:31 +0100 | From | Borislav Petkov <> | Subject | Re: system locks up with CONFIG_SLS=Y; 5.17.0-rc |
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On Wed, Mar 16, 2022 at 12:02:59PM -0700, Dave Hansen wrote: > This hit one of the new int3's in "ASM_RET" in "setc" in > arch/x86/kvm/emulate.c: > > FOP_SETCC(setc) > > Did the extra 'int3' screw up some presumed jump offset or something?
Yap, looks like it. I wonder how no one managed to hit this yet...
Jamie, does this fix it, per chance?
--- diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index f667bd8df533..e88ce4171c4a 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -430,8 +430,11 @@ static int fastop(struct x86_emulate_ctxt *ctxt, fastop_t fop); FOP_END /* Special case for SETcc - 1 instruction per cc */ + +#define SETCC_ALIGN 8 + #define FOP_SETCC(op) \ - ".align 4 \n\t" \ + ".align " __stringify(SETCC_ALIGN) " \n\t" \ ".type " #op ", @function \n\t" \ #op ": \n\t" \ ASM_ENDBR \ @@ -1049,7 +1052,7 @@ static int em_bsr_c(struct x86_emulate_ctxt *ctxt) static __always_inline u8 test_cc(unsigned int condition, unsigned long flags) { u8 rc; - void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf); + void (*fop)(void) = (void *)em_setcc + SETCC_ALIGN * (condition & 0xf); flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF; asm("push %[flags]; popf; " CALL_NOSPEC
-- Regards/Gruss, Boris.
https://people.kernel.org/tglx/notes-about-netiquette
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