From: Andrew Donnellan <andrew.donnellan@xxxxxxxxxxx> This patch has been added to the 3.18 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 949e9b827eb4736d96df520c67d07a54c64e99b8 ] In eeh_pci_enable(), after making the request to set the new options, we call eeh_ops->wait_state() to check that the request finished successfully. At the moment, if eeh_ops->wait_state() returns 0, we return 0 without checking that it reflects the expected outcome. This can lead to callers further up the chain incorrectly assuming the slot has been successfully unfrozen and continuing to attempt recovery. On powernv, this will occur if pnv_eeh_get_pe_state() or pnv_eeh_get_phb_state() return 0, which in turn occurs if the relevant OPAL call returns OPAL_EEH_STOPPED_MMIO_DMA_FREEZE or OPAL_EEH_PHB_ERROR respectively. On pseries, this will occur if pseries_eeh_get_state() returns 0, which in turn occurs if RTAS reports that the PE is in the MMIO Stopped and DMA Stopped states. Obviously, none of these cases represent a successful completion of a request to thaw MMIO or DMA. Fix the check so that a wait_state() return value of 0 won't be considered successful for the EEH_OPT_THAW_MMIO or EEH_OPT_THAW_DMA cases. Signed-off-by: Andrew Donnellan <andrew.donnellan@xxxxxxxxxxx> Acked-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx> Reviewed-by: Daniel Axtens <dja@xxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> --- arch/powerpc/kernel/eeh.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 2248a19..f8402e1 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -646,7 +646,7 @@ int eeh_pci_enable(struct eeh_pe *pe, int function) /* Check if the request is finished successfully */ if (active_flag) { rc = eeh_ops->wait_state(pe, PCI_BUS_RESET_WAIT_MSEC); - if (rc <= 0) + if (rc < 0) return rc; if (rc & active_flag) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html