Commit 433e2f30 authored by Committed by Russell King
ARM: 7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK"
This reverts commit 6b5c8045. Conflicts: arch/arm/kernel/ptrace.c The new syscall restarting code can lead to problems if we take an interrupt in userspace just before restarting the svc instruction. If a signal is delivered when returning from the interrupt, the TIF_SYSCALL_RESTARTSYS will remain set and cause any syscalls executed from the signal handler to be treated as a restart of the previously interrupted system call. This includes the final sigreturn call, meaning that we may fail to exit from the signal context. Furthermore, if a system call made from the signal handler requires a restart via the restart_block, it is possible to clear the thread flag and fail to restart the originally interrupted system call. The right solution to this problem is to perform the restarting in the kernel, avoiding the possibility of handling a further signal before the restart is complete. Since we're almost at -rc6, let's revert the new method for now and aim for in-kernel restarting at a later date. Acked-by: Catalin Marinas <firstname.lastname@example.org> Signed-off-by: Will Deacon <email@example.com> Signed-off-by: Russell King <firstname.lastname@example.org>
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