The following patch was tested and seemed to avoid the warning. Howver I am not completely sure that none of the later functions need to be protected with spinlocks. Though it feels ok. But maybe someone can do some sanity checking. Thanks, Stefan >From d8c94332b8c7422c9c3e20d236f7ba6f59170408 Mon Sep 17 00:00:00 2001 From: Stefan Bader <stefan.bader@xxxxxxxxxxxxx> Date: Wed, 24 Mar 2010 17:06:05 +0000 Subject: [PATCH] sym53c8xx_2: Avoid calling __sym_mfree with irqs disabled BugLink: http://bugs.launchpad.net/bugs/458201 Testing disk hotswap in kvm produced the following warning when removing an inactive drive from the vm. Looking at the code it is __sym_mfree_dma, that disables irqs and then calls __sym_mfree which at some point ends up at code which checks for irqs disabled. WARNING: at /build/buildd/linux-2.6.32/arch/x86/include/asm/dma-mapping.h:154 ___free_dma_mem_cluster+0x102/0x110() Hardware name: Bochs Pid: 17, comm: kacpi_notify Not tainted 2.6.32-16-server #25-Ubuntu Call Trace: [<ffffffff81064f9b>] warn_slowpath_common+0x7b/0xc0 [<ffffffff81064ff4>] warn_slowpath_null+0x14/0x20 [<ffffffff8139a2a2>] ___free_dma_mem_cluster+0x102/0x110 [<ffffffff8139a072>] __sym_mfree+0xd2/0x100 [<ffffffff8139a109>] __sym_mfree_dma+0x69/0x100 [<ffffffff8139245f>] sym_hcb_free+0x8f/0x1f0 [<ffffffff8138fa96>] sym_free_resources+0x46/0x90 [<ffffffff8138fb93>] sym_detach+0xb3/0xe0 [<ffffffff8138fbfb>] sym2_remove+0x3b/0x60 Signed-off-by: Stefan Bader <stefan.bader@xxxxxxxxxxxxx> CC: stable@xxxxxxxxxx --- drivers/scsi/sym53c8xx_2/sym_malloc.c | 5 ++--- 1 files changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/sym53c8xx_2/sym_malloc.c b/drivers/scsi/sym53c8xx_2/sym_malloc.c index 883cac1..006a079 100644 --- a/drivers/scsi/sym53c8xx_2/sym_malloc.c +++ b/drivers/scsi/sym53c8xx_2/sym_malloc.c @@ -339,15 +339,14 @@ void __sym_mfree_dma(m_pool_ident_t dev_dmat, void *m, int size, char *name) spin_lock_irqsave(&sym53c8xx_lock, flags); mp = ___get_dma_pool(dev_dmat); + spin_unlock_irqrestore(&sym53c8xx_lock, flags); if (!mp) - goto out; + return; __sym_mfree(mp, m, size, name); #ifdef SYM_MEM_FREE_UNUSED if (!mp->nump) ___del_dma_pool(mp); #endif - out: - spin_unlock_irqrestore(&sym53c8xx_lock, flags); } /* -- 1.6.3.3 -- To unsubscribe from this list: 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
