[+cc arm64 folks, LKML: This conversation is about this patch: https://lore.kernel.org/linux-pci/20180918235848.26694-3-keith.busch@xxxxxxxxx which fixes some PCIe AER error injection bugs, but also makes the error injector dependent on DYNAMIC_FTRACE_WITH_REGS, which not all arches support. Note that this question is only about the error *injection* module used for testing. It doesn't affect AER support itself.] On Thu, Oct 04, 2018 at 04:11:37PM -0600, Keith Busch wrote: > On Thu, Oct 04, 2018 at 04:40:15PM -0500, Bjorn Helgaas wrote: > > On Tue, Sep 18, 2018 at 05:58:36PM -0600, Keith Busch wrote: > > > I ran into a lot of trouble testing error handling, and this series is > > > just trying to simplify some things. The first 4 fix up aer_inject, and > > > the rest are cleanup to make better use of kernel APIs. > > > > > > Keith Busch (12): > > > PCI: Set PCI bus accessors to noinline > > > PCI/AER: Covertly inject errors > > > PCI/AER: Reuse existing service device lookup > > > PCI/AER: Abstract AER interrupt handling > > > PCI/AER: Remove dead code > > > PCI/AER: Remove error source from aer struct > > > PCI/AER: Use kfifo for tracking events > > > PCI/AER: Use kfifo helper inserting locked elements > > > PCI/AER: Don't read upstream ports below fatal errors > > > PCI/AER: Use threaded IRQ for bottom half > > > PCI/AER: Use managed resource allocations > > > PCI/pciehp: Use device managed allocations > > > > > > drivers/pci/access.c | 4 +- > > > drivers/pci/hotplug/pciehp_core.c | 14 +- > > > drivers/pci/hotplug/pciehp_hpc.c | 48 ++---- > > > drivers/pci/pcie/Kconfig | 2 +- > > > drivers/pci/pcie/aer.c | 219 ++++++--------------------- > > > drivers/pci/pcie/aer_inject.c | 306 ++++++++++++++++++++------------------ > > > drivers/pci/pcie/portdrv.h | 4 - > > > drivers/pci/pcie/portdrv_core.c | 1 + > > > 8 files changed, 227 insertions(+), 371 deletions(-) > > > > Thanks a lot for doing this! I applied these to pci/hotplug for > > v4.20, except for "PCI/AER: Don't read upstream ports below fatal > > errors", which seems to be already there via another posting, and > > "PCI/pciehp: Use device managed allocations", which needs a few > > tweaks. > > Sounds good, and thanks for applying! > > In case this went unnoticed, patch 2's aer_inject using ftrace hooks > to pci config accessors is really cool and fixes several kernel crashes > I encountered, but it may not work on every architecture. I'm not sure > how widely aer_inject is used, so maybe there are no concerns with the > DYNAMIC_FTRACE_WITH_REGS dependency, but I just want to reemphasize that > dependency in case there are valid objections. Oh, indeed, I hadn't noticed this arch dependency. AFAICT, the new DYNAMIC_FTRACE_WITH_REGS dependency means aer_inject will work only on these arches: arm # if (!XIP_KERNEL) && !CPU_ENDIAN_BE32 && MMU powerpc # if PPC64 && CPU_LITTLE_ENDIAN riscv # ARCH_RV64I only s390 x86 Notably missing is arm64, which has DYNAMIC_FTRACE but not DYNAMIC_FTRACE_WITH_REGS. Bjorn
