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kernel: separate state for trace-deferred syscalls

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state is usually not in p_reg any more with sysenter/syscall trap entries,
so when saving/restarting do_ipc invocations the state has to be remembered
explicitly.
This commit is contained in:
Ben Gras 2013-01-04 17:14:31 +00:00
parent 7f1018b145
commit 51a3e84a97
3 changed files with 11 additions and 1 deletions
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3
kernel/arch/i386/arch_system.c
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@ -491,8 +491,9 @@ void arch_do_syscall(struct proc *proc)
/* do_ipc assumes that it's running because of the current process */
assert(proc == get_cpulocal_var(proc_ptr));
/* Make the system call, for real this time. */
assert(proc->p_misc_flags & MF_SC_DEFER);
proc->p_reg.retreg =
do_ipc(proc->p_reg.cx, proc->p_reg.retreg, proc->p_reg.bx);
do_ipc(proc->p_defer.r1, proc->p_defer.r2, proc->p_defer.r3);
}
struct proc * arch_finish_switch_to_user(void)

4
kernel/proc.c
View file

@ -546,7 +546,11 @@ int do_ipc(reg_t r1, reg_t r2, reg_t r3)
* input message. Postpone the entire system call.
*/
caller_ptr->p_misc_flags &= ~MF_SC_TRACE;
assert(!(caller_ptr->p_misc_flags & MF_SC_DEFER));
caller_ptr->p_misc_flags |= MF_SC_DEFER;
caller_ptr->p_defer.r1 = r1;
caller_ptr->p_defer.r2 = r2;
caller_ptr->p_defer.r3 = r3;
/* Signal the "enter system call" event. Block the process. */
cause_sig(proc_nr(caller_ptr), SIGTRAP);

5
kernel/proc.h
View file

@ -121,6 +121,11 @@ struct proc {
int p_found; /* consistency checking variables */
int p_magic; /* check validity of proc pointers */
/* if MF_SC_DEFER is set, this struct is valid and contains the
* do_ipc() arguments that are still to be executed
*/
struct { reg_t r1, r2, r3; } p_defer;
#if DEBUG_TRACE
int p_schedules;
#endif