Commit fd735410 authored Apr 27, 2008 by David S. Miller

sparc64: Fix accidental syscall restart on child return from clone/fork/vfork.



This fixes a regression added by
238468b2 ("[SPARC64]: Use trap type
stored in pt_regs to handle syscall restart.")

Because we now encode the "returning from syscall" status in the
pt_regs area, we have to be mindful to zap it out in the child
of a fork.

During a parallel kernel build I saw an accidental -EINTR return
from vfork() in 'make' because of this bug.

Signed-off-by: David S. Miller <davem@davemloft.net>

parent 90888816

arch/sparc64/kernel/process.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -591,6 +591,12 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
		if (clone_flags & CLONE_SETTLS)
		t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];

		/* We do not want to accidently trigger system call restart
		* handling in the new thread. Therefore, clear out the trap
		* type, which will make pt_regs_regs_is_syscall() return false.
		*/
		pt_regs_clear_trap_type(t->kregs);

		return 0;
		}