MN10300: Enable IRQs more in system call exit work path (d17fc238) · Commits · 戴 / test

Enable IRQs when calling schedule() for TIF_NEED_RESCHED and do_notify_resume(). If interrupts are enabled during do_notify_resume(), a warning can be seen (see lower down). Whilst we're at it, resume_userspace can be made local to entry.S as it is not called outside of there and it can be merged with the part of work_resched that occurs after schedule() is called. WARNING: at kernel/softirq.c:160 local_bh_enable+0x42/0xa0() Call Trace: local_bh_enable+0x42/0xa0 unix_release_sock+0x86/0x23c unix_release+0x20/0x28 sock_release+0x17/0x88 sock_close+0x20/0x28 __fput+0xc9/0x1fc ____fput+0xb/0x10 task_work_run+0x64/0x78 do_notify_resume+0x53d/0x544 work_notifysig+0xa/0xc Signed-off-by:

David Howells <dhowells@redhat.com> Acked-by:

Ken Cox <jkc@redhat.com> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

arch/mn10300/kernel/entry.S

+5 −13

Original line number	Diff line number	Diff line
		@@ -108,10 +108,10 @@ syscall_exit_work:
		and EPSW_nSL,d0
		beq resume_kernel # returning to supervisor mode

		btst _TIF_SYSCALL_TRACE,d2
		beq work_pending
		LOCAL_IRQ_ENABLE # could let syscall_trace_exit() call
		# schedule() instead
		btst _TIF_SYSCALL_TRACE,d2
		beq work_pending
		mov fp,d0
		call syscall_trace_exit[],0 # do_syscall_trace(regs)
		jmp resume_userspace
		@@ -124,6 +124,7 @@ work_pending:
		work_resched:
		call schedule[],0

		resume_userspace:
		# make sure we don't miss an interrupt setting need_resched or
		# sigpending between sampling and the rti
		LOCAL_IRQ_DISABLE
		@@ -132,6 +133,8 @@ work_resched:
		mov (TI_flags,a2),d2
		btst _TIF_WORK_MASK,d2
		beq restore_all

		LOCAL_IRQ_ENABLE
		btst _TIF_NEED_RESCHED,d2
		bne work_resched

		@@ -170,17 +173,6 @@ ret_from_intr:
		and EPSW_nSL,d0
		beq resume_kernel # returning to supervisor mode

		ENTRY(resume_userspace)
		# make sure we don't miss an interrupt setting need_resched or
		# sigpending between sampling and the rti
		LOCAL_IRQ_DISABLE

		# is there any work to be done on int/exception return?
		mov (TI_flags,a2),d2
		btst _TIF_WORK_MASK,d2
		bne work_pending
		jmp restore_all

		#ifdef CONFIG_PREEMPT
		ENTRY(resume_kernel)
		LOCAL_IRQ_DISABLE

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