aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorPavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>2018-02-27 12:51:41 +0300
committerPaolo Bonzini <pbonzini@redhat.com>2018-03-12 16:12:50 +0100
commit5f3bdfd4fa33255542a4b6249913d9ffb11b44f9 (patch)
treed7c0bf556e58bb160a6f2e59b9be85198fc9e60a
parentac64273c66ab136c44043259162a89ec89d21e22 (diff)
cpu-exec: fix exception_index handling
Function cpu_handle_interrupt calls cc->cpu_exec_interrupt to process pending hardware interrupts. Under the hood cpu_exec_interrupt uses cpu->exception_index to pass information to the internal function which is usually common for exception and interrupt processing. But this value is not reset after return and may be processed again by cpu_handle_exception. This does not happen due to overwriting the exception_index at the end of cpu_handle_interrupt. But this branch may also overwrite the valid exception_index in some cases. Therefore this patch: 1. resets exception_index just after the call to cpu_exec_interrupt 2. prevents overwriting the meaningful value of exception_index Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20180227095140.1060.61357.stgit@pasha-VirtualBox> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
-rw-r--r--accel/tcg/cpu-exec.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index 280200f737..9cc697205c 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -585,6 +585,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
else {
if (cc->cpu_exec_interrupt(cpu, interrupt_request)) {
replay_interrupt();
+ cpu->exception_index = -1;
*last_tb = NULL;
}
/* The target hook may have updated the 'cpu->interrupt_request';
@@ -606,7 +607,9 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
if (unlikely(atomic_read(&cpu->exit_request)
|| (use_icount && cpu->icount_decr.u16.low + cpu->icount_extra == 0))) {
atomic_set(&cpu->exit_request, 0);
- cpu->exception_index = EXCP_INTERRUPT;
+ if (cpu->exception_index == -1) {
+ cpu->exception_index = EXCP_INTERRUPT;
+ }
return true;
}