AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity
763fe0addb
kernel_optimize_test/arch/powerpc
History
Gavin Shan 763fe0addb powerpc/powernv: Fix IOMMU group lost 
When we take full hotplug to recover from EEH errors, PCI buses
could be involved. For the case, the child devices of involved
PCI buses can't be attached to IOMMU group properly, which is
caused by commit 3f28c5a ("powerpc/powernv: Reduce multi-hit of
iommu_add_device()").

When adding the PCI devices of the newly created PCI buses to
the system, the IOMMU group is expected to be added in (C).
(A) fails to bind the IOMMU group because bus->is_added is
false. (B) fails because the device doesn't have binding IOMMU
table yet. bus->is_added is set to true at end of (C) and
pdev->is_added is set to true at (D).

   pcibios_add_pci_devices()
      pci_scan_bridge()
         pci_scan_child_bus()
            pci_scan_slot()
               pci_scan_single_device()
                  pci_scan_device()
                  pci_device_add()
                     pcibios_add_device()           A: Ignore
                     device_add()                   B: Ignore
                  pcibios_fixup_bus()
                     pcibios_setup_bus_devices()
                        pcibios_setup_device()      C: Hit
      pcibios_finish_adding_to_bus()
         pci_bus_add_devices()
            pci_bus_add_device()                    D: Add device

If the parent PCI bus isn't involved in hotplug, the IOMMU
group is expected to be bound in (B). (A) should fail as the
sysfs entries aren't populated.

The patch fixes the issue by reverting commit 3f28c5a and remove
WARN_ON() in iommu_add_device() to allow calling the function
even the specified device already has associated IOMMU group.

Cc: <stable@vger.kernel.org>  # 3.16+
Reported-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13 15:13:42 +10:00
..
boot Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2014-08-07 08:50:34 -07:00
configs Here are the PPC and ARM changes for KVM, which I separated because 2014-08-07 11:35:30 -07:00
crypto
include powerpc: Add smp_mb() to arch_spin_is_locked() 2014-08-13 15:13:26 +10:00
kernel powerpc/powernv: Fix IOMMU group lost 2014-08-13 15:13:42 +10:00
kvm Here are the PPC and ARM changes for KVM, which I separated because 2014-08-07 11:35:30 -07:00
lib powerpc: Add smp_mb()s to arch_spin_unlock_wait() 2014-08-13 15:13:27 +10:00
math-emu
mm powerpc/nohash: Split __early_init_mmu() into boot and secondary 2014-08-13 15:13:25 +10:00
net net: filter: split 'struct sk_filter' into socket and bpf parts 2014-08-02 15:03:58 -07:00
oprofile powerpc: Remove oprofile RS64 support 2014-07-28 14:10:25 +10:00
perf Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2014-08-07 08:50:34 -07:00
platforms powerpc/powernv: Fix IOMMU group lost 2014-08-13 15:13:42 +10:00
sysdev Merge remote-tracking branch 'scott/next' into next 2014-08-05 14:13:41 +10:00
xmon powerpc: Remove MMU_FTR_SLB 2014-07-28 14:10:23 +10:00
Kconfig kexec: load and relocate purgatory at kernel load time 2014-08-08 15:57:32 -07:00
Kconfig.debug Patch queue for ppc - 2014-08-01 2014-08-05 09:58:11 +02:00
Makefile
relocs_check.pl