Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx> writes: > Hi Krishna, > > On 6/24/24 7:09 AM, Krishna Kumar wrote: >> Description of the problem: The hotplug driver for powerpc >> (pci/hotplug/pnv_php.c) gives kernel crash when we try to >> hot-unplug/disable the PCIe switch/bridge from the PHB. >> >> Root Cause of Crash: The crash is due to the reason that, though the msi >> data structure has been released during disable/hot-unplug path and it >> has been assigned with NULL, still during unregistartion the code was >> again trying to explicitly disable the msi which causes the Null pointer >> dereference and kernel crash. >> >> Proposed Fix : The fix is to correct the check during unregistration path >> so that the code should not try to invoke pci_disable_msi/msix() if its >> data structure is already freed. >> >> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> >> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> >> Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> >> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxx> >> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> >> Cc: Gaurav Batra <gbatra@xxxxxxxxxxxxx> >> Cc: Nathan Lynch <nathanl@xxxxxxxxxxxxx> >> Cc: Brian King <brking@xxxxxxxxxxxxxxxxxx> >> >> Signed-off-by: Krishna Kumar <krishnak@xxxxxxxxxxxxx> > > As with v1, I can confirm that this patch solves the panic encountered > when hotplugging PCIe bridges on POWER9. Was the panic reported anywhere? So we can link to the report in the commit. cheers
