From 4fb0f76d8cf4f7a3ffc36dd5e1bc8ca977b68824 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 26 Jun 2006 00:26:12 -0700 Subject: [PATCH] [PATCH] Fix IDE locking error This bit us a few kernels ago, and for some reason never made it's way upstream. https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=144743 Kernel panic - not syncing: drivers/ide/pci/piix.c:231: spin_lock(drivers/ide/ide.c:c03cef28) already locked by driver/ide/ide-iops.c/1153. Signed-off-by: Dave Jones Cc: Bartlomiej Zolnierkiewicz Cc: Dave Jones Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/ide/pci/piix.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/ide/pci/piix.c b/drivers/ide/pci/piix.c index e9b83e1a302..7fac6f57b5d 100644 --- a/drivers/ide/pci/piix.c +++ b/drivers/ide/pci/piix.c @@ -222,6 +222,8 @@ static void piix_tune_drive (ide_drive_t *drive, u8 pio) unsigned long flags; u16 master_data; u8 slave_data; + static DEFINE_SPINLOCK(tune_lock); + /* ISP RTC */ u8 timings[][2] = { { 0, 0 }, { 0, 0 }, @@ -230,7 +232,13 @@ static void piix_tune_drive (ide_drive_t *drive, u8 pio) { 2, 3 }, }; pio = ide_get_best_pio_mode(drive, pio, 5, NULL); - spin_lock_irqsave(&ide_lock, flags); + + /* + * Master vs slave is synchronized above us but the slave register is + * shared by the two hwifs so the corner case of two slave timeouts in + * parallel must be locked. + */ + spin_lock_irqsave(&tune_lock, flags); pci_read_config_word(dev, master_port, &master_data); if (is_slave) { master_data = master_data | 0x4000; @@ -250,7 +258,7 @@ static void piix_tune_drive (ide_drive_t *drive, u8 pio) pci_write_config_word(dev, master_port, master_data); if (is_slave) pci_write_config_byte(dev, slave_port, slave_data); - spin_unlock_irqrestore(&ide_lock, flags); + spin_unlock_irqrestore(&tune_lock, flags); } /** -- 2.20.1