We have seen that when kvm-unit-tests runs with kgdb enabled, the kernel halts on the debugger during the KVM x86 instruction emulation that performs a test of a division by zero, and also during fwait.
This patch adds calls that temporarily disable the debugger trap. Signed-off-by: Dan Aloni <[email protected]> Signed-off-by: Muli Ben-Yehuda <[email protected]> --- arch/x86/kvm/emulate.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 07ffca0..05e8509 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -24,6 +24,7 @@ #include "kvm_cache_regs.h" #include <linux/module.h> #include <asm/kvm_emulate.h> +#include <asm/kgdb.h> #include <linux/stringify.h> #include "x86.h" @@ -4438,6 +4439,7 @@ static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt) { bool fault = false; + kgdb_ll_local_disable(); ctxt->ops->get_fpu(ctxt); asm volatile("1: fwait \n\t" "2: \n\t" @@ -4449,6 +4451,7 @@ static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt) _ASM_EXTABLE(1b, 3b) : [fault]"+qm"(fault)); ctxt->ops->put_fpu(ctxt); + kgdb_ll_local_enable(); if (unlikely(fault)) return emulate_exception(ctxt, MF_VECTOR, 0, false); @@ -4468,10 +4471,14 @@ static int fastop(struct x86_emulate_ctxt *ctxt, void (*fop)(struct fastop *)) ulong flags = (ctxt->eflags & EFLAGS_MASK) | X86_EFLAGS_IF; if (!(ctxt->d & ByteOp)) fop += __ffs(ctxt->dst.bytes) * FASTOP_SIZE; + + kgdb_ll_local_disable(); asm("push %[flags]; popf; call *%[fastop]; pushf; pop %[flags]\n" : "+a"(ctxt->dst.val), "+d"(ctxt->src.val), [flags]"+D"(flags), [fastop]"+S"(fop) : "c"(ctxt->src2.val)); + kgdb_ll_local_enable(); + ctxt->eflags = (ctxt->eflags & ~EFLAGS_MASK) | (flags & EFLAGS_MASK); if (!fop) /* exception is returned in fop variable */ return emulate_de(ctxt); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
