kernel.git/arch/powerpc/platforms, branch linux-4.8.y

powerpc/pseries: Fix stack corruption in htpe code

2016-10-28T07:45:22Z

commit 05af40e885955065aee8bb7425058eb3e1adca08 upstream. This commit fixes a stack corruption in the pseries specific code dealing with the huge pages. In __pSeries_lpar_hugepage_invalidate() the buffer used to pass arguments to the hypervisor is not large enough. This leads to a stack corruption where a previously saved register could be corrupted leading to unexpected result in the caller, like the following panic: Oops: Kernel access of bad area, sig: 11 [#1] SMP NR_CPUS=2048 NUMA pSeries Modules linked in: virtio_balloon ip_tables x_tables autofs4 virtio_blk 8139too virtio_pci virtio_ring 8139cp virtio CPU: 11 PID: 1916 Comm: mmstress Not tainted 4.8.0 #76 task: c000000005394880 task.stack: c000000005570000 NIP: c00000000027bf6c LR: c00000000027bf64 CTR: 0000000000000000 REGS: c000000005573820 TRAP: 0300 Not tainted (4.8.0) MSR: 8000000000009033 CR: 84822884 XER: 20000000 CFAR: c00000000010a924 DAR: 420000000014e5e0 DSISR: 40000000 SOFTE: 1 GPR00: c00000000027bf64 c000000005573aa0 c000000000e02800 c000000004447964 GPR04: c00000000404de18 c000000004d38810 00000000042100f5 00000000f5002104 GPR08: e0000000f5002104 0000000000000001 042100f5000000e0 00000000042100f5 GPR12: 0000000000002200 c00000000fe02c00 c00000000404de18 0000000000000000 GPR16: c1ffffffffffe7ff 00003fff62000000 420000000014e5e0 00003fff63000000 GPR20: 0008000000000000 c0000000f7014800 0405e600000000e0 0000000000010000 GPR24: c000000004d38810 c000000004447c10 c00000000404de18 c000000004447964 GPR28: c000000005573b10 c000000004d38810 00003fff62000000 420000000014e5e0 NIP [c00000000027bf6c] zap_huge_pmd+0x4c/0x470 LR [c00000000027bf64] zap_huge_pmd+0x44/0x470 Call Trace: [c000000005573aa0] [c00000000027bf64] zap_huge_pmd+0x44/0x470 (unreliable) [c000000005573af0] [c00000000022bbd8] unmap_page_range+0xcf8/0xed0 [c000000005573c30] [c00000000022c2d4] unmap_vmas+0x84/0x120 [c000000005573c80] [c000000000235448] unmap_region+0xd8/0x1b0 [c000000005573d80] [c0000000002378f0] do_munmap+0x2d0/0x4c0 [c000000005573df0] [c000000000237be4] SyS_munmap+0x64/0xb0 [c000000005573e30] [c000000000009560] system_call+0x38/0x108 Instruction dump: fbe1fff8 fb81ffe0 7c7f1b78 7ca32b78 7cbd2b78 f8010010 7c9a2378 f821ffb1 7cde3378 4bfffea9 7c7b1b79 41820298 48000130 7fa5eb78 7fc4f378 Most of the time, the bug is surfacing in a caller up in the stack from __pSeries_lpar_hugepage_invalidate() which is quite confusing. This bug is pending since v3.11 but was hidden if a caller of the caller of __pSeries_lpar_hugepage_invalidate() has pushed the corruped register (r18 in this case) in the stack and is not using it until restoring it. GCC 6.2.0 seems to raise it more frequently. This commit also change the definition of the parameter buffer in pSeries_lpar_flush_hash_range() to rely on the global define PLPAR_HCALL9_BUFSIZE (no functional change here). Fixes: 1a5272866f87 ("powerpc: Optimize hugepage invalidate") Signed-off-by: Laurent Dufour Reviewed-by: Aneesh Kumar K.V Acked-by: Balbir Singh Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/powernv: Use CPU-endian PEST in pnv_pci_dump_p7ioc_diag_data()

2016-10-28T07:45:22Z

commit 5adaf8629b193f185ca5a1665b9e777a0579f518 upstream. This fixes the warnings reported from sparse: pci.c:312:33: warning: restricted __be64 degrades to integer pci.c:313:33: warning: restricted __be64 degrades to integer Fixes: cee72d5bb489 ("powerpc/powernv: Display diag data on p7ioc EEH errors") Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/powernv: Use CPU-endian hub diag-data type in pnv_eeh_get_and_dump_hub_diag()

2016-10-28T07:45:21Z

commit a7032132d7560a8434e1f54b71efd7fa20f073bd upstream. The hub diag-data type is filled with big-endian data by OPAL call opal_pci_get_hub_diag_data(). We need convert it to CPU-endian value before using it. The issue is reported by sparse as pointed by Michael Ellerman: eeh-powernv.c:1309:21: warning: restricted __be16 degrades to integer This converts hub diag-data type to CPU-endian before using it in pnv_eeh_get_and_dump_hub_diag(). Fixes: 2a485ad7c88d ("powerpc/powernv: Drop PHB operation next_error()") Suggested-by: Michael Ellerman Signed-off-by: Gavin Shan Reviewed-by: Russell Currey Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Null check uses of eeh_pe_bus_get

2016-10-28T07:45:21Z

commit 04fec21c06e35b169a83e75a84a015ab4606bf5e upstream. eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE. Some callers don't check this, and can cause a null pointer dereference under certain circumstances. Fix this by checking NULL everywhere eeh_pe_bus_get() is called. Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event") Signed-off-by: Russell Currey Reviewed-by: Andrew Donnellan Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/powernv: Pass CPU-endian PE number to opal_pci_eeh_freeze_clear()

2016-10-28T07:45:21Z

commit d63e51b31e0b655ed0f581b8a8fd4c4b4f8d1919 upstream. The PE number (@frozen_pe_no), filled by opal_pci_next_error() is in big-endian format. It should be converted to CPU-endian before it is passed to opal_pci_eeh_freeze_clear() when clearing the frozen state if the PE is invalid one. As Michael Ellerman pointed out, the issue is also detected by sparse: eeh-powernv.c:1541:41: warning: incorrect type in argument 2 (different base types) This passes CPU-endian PE number to opal_pci_eeh_freeze_clear() and it should be part of commit <0f36db77643b> ("powerpc/eeh: Fix wrong printed PE number"), which was merged to 4.3 kernel. Fixes: 71b540adffd9 ("powerpc/powernv: Don't escalate non-existing frozen PE") Suggested-by: Paul Mackerras Signed-off-by: Gavin Shan Reviewed-by: Russell Currey Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/powernv/pci: Fix m64 checks for SR-IOV and window alignment

2016-09-21T04:04:13Z

Commit 5958d19a143e checks for prefetchable m64 BARs by comparing the addresses instead of using resource flags. This broke SR-IOV as the m64 check in pnv_pci_ioda_fixup_iov_resources() fails. The condition in pnv_pci_window_alignment() also changed to checking only IORESOURCE_MEM_64 instead of both IORESOURCE_MEM_64 and IORESOURCE_PREFETCH. Revert these cases to the previous behaviour, adding a new helper function to do so. This is named pnv_pci_is_m64_flags() to make it clear this function is only looking at resource flags and should not be relied on for non-SRIOV resources. Fixes: 5958d19a143e ("Fix incorrect PE reservation attempt on some 64-bit BARs") Reported-by: Alexey Kardashevskiy Signed-off-by: Russell Currey Tested-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman

powerpc/powernv/pci: Fix missed TCE invalidations that should fallback to OPAL

2016-09-15T07:05:11Z

In commit f0228c413011 ("powerpc/powernv/pci: Fallback to OPAL for TCE invalidations"), we added logic to fallback to OPAL for doing TCE invalidations if we can't do it in Linux. Ben sent a v2 of the patch, containing these additional call sites, but I had already applied v1 and didn't notice. So fix them now. Fixes: f0228c413011 ("powerpc/powernv/pci: Fallback to OPAL for TCE invalidations") Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc/powernv: Detach from PE on releasing PCI device

2016-09-15T03:53:19Z

The PCI hotplug can be part of EEH error recovery. The @pdn and the device's PE number aren't removed and added afterwords. The PE number in @pdn should be set to an invalid one. Otherwise, the PE's device count is decreased on removing devices while failing to be increased on adding devices. It leads to unbalanced PE's device count and make normal PCI hotplug path broken. Fixes: c5f7700bbd2e ("powerpc/powernv: Dynamically release PE") Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman

powerpc/powernv: Fix the state of root PE

2016-09-14T01:40:09Z

The PE for root bus (root PE) can be removed because of PCI hot remove in EEH recovery path for fenced PHB error. We need update @phb->root_pe_populated accordingly so that the root PE can be populated again in forthcoming PCI hot add path. Also, the PE shouldn't be destroyed as it's global and reserved resource. Fixes: c5f7700bbd2e ("powerpc/powernv: Dynamically release PE") Reported-by: Frederic Barrat Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman

powerpc/powernv: Fix corrupted PE allocation bitmap on releasing PE

2016-09-08T03:12:52Z

In pnv_ioda_free_pe(), the PE object (including the associated PE number) is cleared before resetting the corresponding bit in the PE allocation bitmap. It means PE#0 is always released to the bitmap wrongly. This fixes above issue by caching the PE number before the PE object is cleared. Fixes: 1e9167726c41 ("powerpc/powernv: Use PE instead of number during setup and release" Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Gavin Shan Signed-off-by: Michael Ellerman