diff options
Diffstat (limited to 'hurd')
| -rw-r--r-- | hurd/hurdsig.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/hurd/hurdsig.c b/hurd/hurdsig.c index ea79ffb597..5ff0a91fea 100644 --- a/hurd/hurdsig.c +++ b/hurd/hurdsig.c @@ -415,6 +415,7 @@ _hurdsig_abort_rpcs (struct hurd_sigstate *ss, int signo, int sigthread, void (*reply) (void)) { extern const void _hurd_intr_rpc_msg_about_to; + extern const void _hurd_intr_rpc_msg_setup_done; extern const void _hurd_intr_rpc_msg_in_trap; mach_port_t rcv_port = MACH_PORT_NULL; mach_port_t intr_port; @@ -434,11 +435,18 @@ _hurdsig_abort_rpcs (struct hurd_sigstate *ss, int signo, int sigthread, && state->basic.PC < (uintptr_t) &_hurd_intr_rpc_msg_in_trap) { /* The thread is about to do the RPC, but hasn't yet entered - mach_msg. Mutate the thread's state so it knows not to try - the RPC. */ - INTR_MSG_BACK_OUT (&state->basic); - MACHINE_THREAD_STATE_SET_PC (&state->basic, - &_hurd_intr_rpc_msg_in_trap); + mach_msg. Importantly, it may have already checked ss->cancel for + the last time before doing the RPC, so setting that is not enough + to make it not enter mach_msg. Instead, mutate the thread's state + so it knows not to try the RPC. + + If the thread is past _hurd_intr_rpc_msg_setup_done, just make it + jump to after the trap, since we know it's safe to do so. Otherwise, + we know that the thread is yet to check for the MACH_SEND_INTERRUPTED + value we set below, and will skip the trap by itself. */ + if (state->basic.PC >= (uintptr_t) &_hurd_intr_rpc_msg_setup_done) + MACHINE_THREAD_STATE_SET_PC (&state->basic, + &_hurd_intr_rpc_msg_in_trap); state->basic.SYSRETURN = MACH_SEND_INTERRUPTED; *state_change = 1; } |