Dear Jingoo Han, > On Tuesday, November 19, 2013 6:03 AM, Bjorn Helgaas wrote: > > On Mon, Nov 18, 2013 at 2:01 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > >> On Mon, Nov 18, 2013 at 6:53 AM, Bjørn Erik Nilsen <ben@xxxxxxxxxxxxxx> wrote: > >>> I just hit an kernel oops related to PCI (in > >>> dw_msi_teardown_irq()/clear_irq() (pcie-designware)) > >>> > >>> Linux version 3.12.0-next-20131105 (bnilsen@bnilsen) (gcc version 4.7.2 > >>> (GCC) ) > >>> > >>> Problem seem to be dereferencing a null pointer returned from > >>> irq_desc_get_msi_desc(desc) (see attached backtrace). > >> > >> Included oops inline for ease of viewing/searching. Jingooo, I assume > >> you'll investigate this. Let me know if otherwise. > > (+cc Marek Vasut, Pratyush Anand, Kishon Vijay Abraham I, > Mohit KUMAR DCG, Ajay KHANDELWAL, Tim Harvey) > > Sorry, I will not investigate this. > > Bjørn Erik Nilsen, > > Would you let us know the ARM platform and LAN card? > If you let us know them, one of these pcie-designware related > people would reproduce and look at the issue. > > Best regards, > Jingoo Han > > >> Unable to handle kernel NULL pointer dereference at virtual address > >> 00000020 pgd = 80004000 > >> [00000020] *pgd=00000000 > >> Internal error: Oops: 17 [#1] SMP ARM > >> Modules linked in: sxdma(O) > >> CPU: 1 PID: 569 Comm: i2cipc.B3 Tainted: G O > >> 3.12.0-next-20131105 #8 task: 9efcb600 ti: 9ec8c000 task.ti: 9ec8c000 > >> PC is at dw_msi_teardown_irq+0x40/0x118 see drivers/pci/host/pcie-designware.c : 336 static void dw_msi_teardown_irq(struct msi_chip *chip, unsigned int irq) 337 { 338 clear_irq(irq); 339 } So, add such a print before the clear_irq() call: pr_err("%i %i\n", chip != NULL, irq); And let us know the result please. Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html