From 6dc659d813fdd1789e605d69d0b8762d284e8c60 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sun, 26 Mar 2006 01:36:54 -0800 Subject: [PATCH] [PATCH] drivers/block/floppy.c: dont free_irq() from irq context free_irq() should not be executed from softirq context. Found by the lock validator. The fix is to push fd_free_irq() into keventd. The code validates fine with this patch applied. (akpm: this is revolting, but so is floppy.c) [akpm@osdl.org: added flush_scheduled_work()] Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/floppy.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 840919b..d3ad908 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -250,6 +250,18 @@ static int irqdma_allocated; #include /* for the compatibility eject ioctl */ #include +/* + * Interrupt freeing also means /proc VFS work - dont do it + * from interrupt context. We push this work into keventd: + */ +static void fd_free_irq_fn(void *data) +{ + fd_free_irq(); +} + +static DECLARE_WORK(fd_free_irq_work, fd_free_irq_fn, NULL); + + static struct request *current_req; static struct request_queue *floppy_queue; static void do_fd_request(request_queue_t * q); @@ -4433,6 +4445,13 @@ static int floppy_grab_irq_and_dma(void) return 0; } spin_unlock_irqrestore(&floppy_usage_lock, flags); + + /* + * We might have scheduled a free_irq(), wait it to + * drain first: + */ + flush_scheduled_work(); + if (fd_request_irq()) { DPRINT("Unable to grab IRQ%d for the floppy driver\n", FLOPPY_IRQ); @@ -4522,7 +4541,7 @@ static void floppy_release_irq_and_dma(void) if (irqdma_allocated) { fd_disable_dma(); fd_free_dma(); - fd_free_irq(); + schedule_work(&fd_free_irq_work); irqdma_allocated = 0; } set_dor(0, ~0, 8); @@ -4633,6 +4652,8 @@ void cleanup_module(void) /* eject disk, if any */ fd_eject(0); + flush_scheduled_work(); /* fd_free_irq() might be pending */ + wait_for_completion(&device_release); } -- 2.7.4