Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 572e6147 authored by Jeff Dike's avatar Jeff Dike Committed by Linus Torvalds
Browse files

[PATCH] uml: add locking to xtime accesses 



do_timer must be called with xtime_lock held.  I'm not sure boot_timer_handler
needs this, however I don't think it hurts: it simply disables irq and takes a
spinlock.

Signed-off-by: default avatarPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 6edb0862

arch/um/kernel/time_kern.c

+8 −2
Original line number Diff line number Diff line
@@ -96,11 +96,15 @@ void time_init_kern(void) 


void do_boot_timer_handler(struct sigcontext * sc)

{

	unsigned long flags;

	struct pt_regs regs;



	CHOOSE_MODE((void) (UPT_SC(&regs.regs) = sc),

		    (void) (regs.regs.skas.is_user = 0));



	write_seqlock_irqsave(&xtime_lock, flags);

	do_timer(&regs);

	write_sequnlock_irqrestore(&xtime_lock, flags);

}



static DEFINE_SPINLOCK(timer_spinlock);
@@ -125,15 +129,17 @@ irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs) 
	unsigned long long nsecs;

	unsigned long flags;



	write_seqlock_irqsave(&xtime_lock, flags);



	do_timer(regs);



	write_seqlock_irqsave(&xtime_lock, flags);

	nsecs = get_time() + local_offset;

	xtime.tv_sec = nsecs / NSEC_PER_SEC;

	xtime.tv_nsec = nsecs - xtime.tv_sec * NSEC_PER_SEC;



	write_sequnlock_irqrestore(&xtime_lock, flags);



	return(IRQ_HANDLED);

	return IRQ_HANDLED;

}



long um_time(int __user *tloc)