On Mon, 7 Nov 2005, Andrew Morton wrote: > Reuben Farrelly <reuben-lkml@xxxxxxxx> wrote: > > > > Debug: sleeping function called from invalid context at include/asm/semaphore.h:99 > > in_atomic():1, irqs_disabled():1 > > [<c0103c46>] dump_stack+0x17/0x19 > > [<c011a173>] __might_sleep+0x9c/0xae > > [<c028f82b>] scsi_disk_get_from_dev+0x15/0x48 > > [<c029006e>] sd_prepare_flush+0x17/0x5a > > [<c027f8ff>] scsi_prepare_flush_fn+0x30/0x33 > > [<c0259da0>] blk_start_pre_flush+0xd5/0x13f > > [<c025936b>] elv_next_request+0x113/0x170 > > [<c027fd45>] scsi_request_fn+0x4b/0x2fd > > [<c025b393>] blk_run_queue+0x2b/0x3c > > [<c027f0b3>] scsi_run_queue+0xa4/0xb6 > > [<c027f11f>] scsi_next_command+0x16/0x19 > > [<c027f1db>] scsi_end_request+0x93/0xc5 > > [<c027f494>] scsi_io_completion+0x141/0x46b > > [<c02901e9>] sd_rw_intr+0x117/0x22b > > [<c027ae5f>] scsi_finish_command+0x7f/0x93 > > [<c027ad43>] scsi_softirq+0xa8/0x11a > > [<c0121eb8>] __do_softirq+0x88/0x141 > > [<c0104fd9>] do_softirq+0x77/0x81 > > ======================= > > [<c012205a>] irq_exit+0x48/0x4a > > [<c0104e84>] do_IRQ+0x74/0xa7 > > [<c010374e>] common_interrupt+0x1a/0x20 > > [<f8918c04>] acpi_processor_idle+0x11f/0x2c7 [processor] > > [<c0100d71>] cpu_idle+0x49/0xa0 > > [<c01002d7>] rest_init+0x37/0x39 > > [<c03fd8c5>] start_kernel+0x166/0x179 > > [<c0100210>] 0xc0100210 > > ah-hah, that's a different trace. > > sd_issue_flush() has been altered to run scsi_disk_get_from_dev(), which > takes a semaphore. It does this from within spinlock and, as we see here, > from within softirq. > > Methinks the people who developed and tested that patch forgot to enable > CONFIG_PREEMPT, CONFIG_DEBUG_KERNEL, CONFIG_DEBUG_SLAB, > CONFIG_DEBUG_SPINLOCK and CONFIG_DEBUG_SPINLOCK_SLEEP. No, believe it or not, all those items are enabled in my .config. What I didn't do was test the patch with anything that would force a call to sd_prepare_flush. In fact, I'm not sure how to do such a thing. I don't know how this should be fixed. James will have to come up with something. Alan Stern - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
