On Wed, 13 Apr 2011, Roedel, Joerg wrote: > On Tue, Apr 12, 2011 at 06:59:27AM -0400, Sergei Shtylyov wrote: > > On 12-04-2011 10:41, Roedel, Joerg wrote: > > > > + if (nb) > > > + pci_dev_put(nb); > > > + if (smbus) > > > + pci_dev_put(amd_chipset.smbus_dev); > > > > Here it is. This pointer is NULL, it should be 'smbus' instead. > > Ok, this is fixed now too. > > From 7ee4b6274f5e4c1f238e9ff4faa0b9a43f5203e2 Mon Sep 17 00:00:00 2001 > From: Joerg Roedel <joerg.roedel@xxxxxxx> > Date: Wed, 6 Apr 2011 13:07:53 +0200 > Subject: [PATCH] USB host: Fix lockdep warning in AMD PLL quirk > > Booting latest kernel on my test machine produces a lockdep > warning from the usb_amd_find_chipset_info() function: > > WARNING: at /data/lemmy/linux.trees.git/kernel/lockdep.c:2465 lockdep_trace_alloc+0x95/0xc2() > Hardware name: Snook > Modules linked in: > Pid: 959, comm: work_for_cpu Not tainted 2.6.39-rc2+ #22 > Call Trace: > [<ffffffff8103c0d4>] warn_slowpath_common+0x80/0x98 > [<ffffffff812387e6>] ? T.492+0x24/0x26 > [<ffffffff8103c101>] warn_slowpath_null+0x15/0x17 > [<ffffffff81068667>] lockdep_trace_alloc+0x95/0xc2 > [<ffffffff810ed9ac>] slab_pre_alloc_hook+0x18/0x3b > [<ffffffff810ef227>] kmem_cache_alloc_trace+0x25/0xba > [<ffffffff812387e6>] T.492+0x24/0x26 > [<ffffffff81238816>] pci_get_subsys+0x2e/0x73 > [<ffffffff8123886c>] pci_get_device+0x11/0x13 > [<ffffffff814082a9>] usb_amd_find_chipset_info+0x3f/0x18a > ... > > It turns out that this function calls pci_get_device under a spin_lock > with irqs disabled, but the pci_get_device function is only allowed in > preemptible context. > > This patch fixes the warning by making all data-structure > modifications on temporal storage and commiting this back > into the visible structure at the end. While at it, this > patch also moves the pci_dev_put calls out of the spinlocks > because this function might sleep too. > > Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
