summaryrefslogtreecommitdiff
AgeCommit message (Collapse)AuthorFilesLines
2019-02-22powerpc/eeh_cache: Add a way to dump the EEH address cacheOliver O'Halloran3-4/+30
Adds a debugfs file that can be read to view the contents of the EEH address cache. This is pretty similar to the existing eeh_addr_cache_print() function, but that function is intended to debug issues inside of the kernel since it's #ifdef`ed out by default, and writes into the kernel log. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22powerpc/eeh_cache: Add pr_debug() prints for insert/removeOliver O'Halloran1-2/+2
The EEH address cache is used to map a physical MMIO address back to a PCI device. It's useful to know when it's being manipulated, but currently this requires recompiling with #define DEBUG set. This is pointless since we have dynamic_debug nowdays, so remove the #ifdef guard and add a pr_debug() for the remove case too. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22powerpc/eeh: Use debugfs_create_u32 for eeh_max_freezesOliver O'Halloran2-19/+4
There's no need to the custom getter/setter functions so we should remove them in favour of using the generic one. While we're here, change the type of eeh_max_freeze to u32 and print the value in decimal rather than hex because printing it in hex makes no sense. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22powerpc: drop unused GENERIC_CSUM Kconfig itemChristophe Leroy2-7/+0
Commit d4fde568a34a ("powerpc/64: Use optimized checksum routines on little-endian") converted last powerpc user of GENERIC_CSUM. This patch does a final cleanup dropping the Kconfig GENERIC_CSUM option which is always 'n', and associated piece of code in asm/checksum.h Fixes: d4fde568a34a ("powerpc/64: Use optimized checksum routines on little-endian") Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22powerpc/64s/hash: Fix assert_slb_presence() use of the slbfee. instructionNicholas Piggin1-0/+5
The slbfee. instruction must have bit 24 of RB clear, failure to do so can result in false negatives that result in incorrect assertions. This is not obvious from the ISA v3.0B document, which only says: The hardware ignores the contents of RB 36:38 40:63 -- p.1032 This patch fixes the bug and also clears all other bits from PPC bit 36-63, which is good practice when dealing with reserved or ignored bits. Fixes: e15a4fea4dee ("powerpc/64s/hash: Add some SLB debugging tests") Cc: stable@vger.kernel.org # v4.20+ Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22powerpc/mm/hash: Increase vmalloc space to 512T with hash MMUMichael Ellerman1-9/+23
This patch updates the kernel non-linear virtual map to 512TB when we're built with 64K page size and are using the hash MMU. We allocate one context for the vmalloc region and hence the max virtual area size is limited by the context map size (512TB for 64K and 64TB for 4K page size). This patch fixes boot failures with large amounts of system RAM where we need large vmalloc space to handle per cpu allocations. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
2019-02-22powerpc/ptrace: Simplify vr_get/set() to avoid GCC warningMichael Ellerman1-2/+8
GCC 8 warns about the logic in vr_get/set(), which with -Werror breaks the build: In function ‘user_regset_copyin’, inlined from ‘vr_set’ at arch/powerpc/kernel/ptrace.c:628:9: include/linux/regset.h:295:4: error: ‘memcpy’ offset [-527, -529] is out of the bounds [0, 16] of object ‘vrsave’ with type ‘union <anonymous>’ [-Werror=array-bounds] arch/powerpc/kernel/ptrace.c: In function ‘vr_set’: arch/powerpc/kernel/ptrace.c:623:5: note: ‘vrsave’ declared here } vrsave; This has been identified as a regression in GCC, see GCC bug 88273. However we can avoid the warning and also simplify the logic and make it more robust. Currently we pass -1 as end_pos to user_regset_copyout(). This says "copy up to the end of the regset". The definition of the regset is: [REGSET_VMX] = { .core_note_type = NT_PPC_VMX, .n = 34, .size = sizeof(vector128), .align = sizeof(vector128), .active = vr_active, .get = vr_get, .set = vr_set }, The end is calculated as (n * size), ie. 34 * sizeof(vector128). In vr_get/set() we pass start_pos as 33 * sizeof(vector128), meaning we can copy up to sizeof(vector128) into/out-of vrsave. The on-stack vrsave is defined as: union { elf_vrreg_t reg; u32 word; } vrsave; And elf_vrreg_t is: typedef __vector128 elf_vrreg_t; So there is no bug, but we rely on all those sizes lining up, otherwise we would have a kernel stack exposure/overwrite on our hands. Rather than relying on that we can pass an explict end_pos based on the sizeof(vrsave). The result should be exactly the same but it's more obviously not over-reading/writing the stack and it avoids the compiler warning. Reported-by: Meelis Roos <mroos@linux.ee> Reported-by: Mathieu Malaterre <malat@debian.org> Cc: stable@vger.kernel.org Tested-by: Mathieu Malaterre <malat@debian.org> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22powerpc/powernv/npu: Remove redundant change_pte() hookPeter Xu1-10/+0
The change_pte() notifier was designed to use as a quick path to update secondary MMU PTEs on write permission changes or PFN changes. For KVM, it could reduce the vm-exits when vcpu faults on the pages that was touched up by KSM. It's not used to do cache invalidations, for example, if we see the notifier will be called before the real PTE update after all (please see set_pte_at_notify that set_pte_at was called later). All the necessary cache invalidation should all be done in invalidate_range() already. Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Alistair Popple <alistair@popple.id.au> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22Merge branch 'topic/ppc-kvm' into nextMichael Ellerman8-91/+54
Merge commits we're sharing with kvm-ppc tree.
2019-02-21powerpc/64s: Better printing of machine check info for guest MCEsPaul Mackerras4-7/+9
This adds an "in_guest" parameter to machine_check_print_event_info() so that we can avoid trying to translate guest NIP values into symbolic form using the host kernel's symbol table. Reviewed-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21KVM: PPC: Book3S HV: Simplify machine check handlingPaul Mackerras5-84/+42
This makes the handling of machine check interrupts that occur inside a guest simpler and more robust, with less done in assembler code and in real mode. Now, when a machine check occurs inside a guest, we always get the machine check event struct and put a copy in the vcpu struct for the vcpu where the machine check occurred. We no longer call machine_check_queue_event() from kvmppc_realmode_mc_power7(), because on POWER8, when a vcpu is running on an offline secondary thread and we call machine_check_queue_event(), that calls irq_work_queue(), which doesn't work because the CPU is offline, but instead triggers the WARN_ON(lazy_irq_pending()) in pnv_smp_cpu_kill_self() (which fires again and again because nothing clears the condition). All that machine_check_queue_event() actually does is to cause the event to be printed to the console. For a machine check occurring in the guest, we now print the event in kvmppc_handle_exit_hv() instead. The assembly code at label machine_check_realmode now just calls C code and then continues exiting the guest. We no longer either synthesize a machine check for the guest in assembly code or return to the guest without a machine check. The code in kvmppc_handle_exit_hv() is extended to handle the case where the guest is not FWNMI-capable. In that case we now always synthesize a machine check interrupt for the guest. Previously, if the host thinks it has recovered the machine check fully, it would return to the guest without any notification that the machine check had occurred. If the machine check was caused by some action of the guest (such as creating duplicate SLB entries), it is much better to tell the guest that it has caused a problem. Therefore we now always generate a machine check interrupt for guests that are not FWNMI-capable. Reviewed-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-21Merge branch 'topic/dma' into nextMichael Ellerman48-1158/+317
Merge hch's big DMA rework series. This is in a topic branch in case he wants to merge it to minimise conflicts.
2019-02-21KVM: PPC: Book3S HV: Context switch AMR on Power9Michael Ellerman1-1/+4
kvmhv_p9_guest_entry() implements a fast-path guest entry for Power9 when guest and host are both running with the Radix MMU. Currently in that path we don't save the host AMR (Authority Mask Register) value, and we always restore 0 on return to the host. That is OK at the moment because the AMR is not used for storage keys with the Radix MMU. However we plan to start using the AMR on Radix to prevent the kernel from reading/writing to userspace outside of copy_to/from_user(). In order to make that work we need to save/restore the AMR value. We only restore the value if it is different from the guest value, which is already in the register when we exit to the host. This should mean we rarely need to actually restore the value when running a modern Linux as a guest, because it will be using the same value as us. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Russell Currey <ruscur@russell.cc>
2019-02-19Merge branch 'fixes' into nextMichael Ellerman15-35/+60
There's a few important fixes in our fixes branch, in particular the pgd/pud_present() one, so merge it now.
2019-02-18powerpc/dma: trim the fat from <asm/dma-mapping.h>Christoph Hellwig6-29/+14
There is no need to provide anything but get_arch_dma_ops to <linux/dma-mapping.h>. More the remaining declarations to <asm/iommu.h> and drop all the includes. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove set_dma_offsetChristoph Hellwig8-20/+11
There is no good reason for this helper, just opencode it. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove get_dma_offsetChristoph Hellwig2-18/+6
Just fold the calculation into __phys_to_dma/__dma_to_phys as those are the only places that should know about it. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: use the generic direct mapping bypassChristoph Hellwig25-222/+16
Now that we've switched all the powerpc nommu and swiotlb methods to use the generic dma_direct_* calls we can remove these ops vectors entirely and rely on the common direct mapping bypass that avoids indirect function calls entirely. This also allows to remove a whole lot of boilerplate code related to setting up these operations. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: use the dma_direct mapping routinesChristoph Hellwig5-120/+32
Switch the streaming DMA mapping and ownership transfer methods to the functionally identical dma_direct_ versions. Factor the cache maintainance helpers into the form expected by the common code for that. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: use the dma-direct allocator for coherent platformsChristoph Hellwig5-92/+9
The generic code allows a few nice things such as node local allocations and dipping into the CMA area. The lookup of the right zone for a given dma mask works a little different, but the results should be the same. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18swiotlb: remove swiotlb_dma_supportedChristoph Hellwig3-16/+1
The only user left is powerpc, but even there the generic dma-direct version works just as well, given that we guarantee that the swiotlb buffer must always be addressable. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove dma_nommu_dma_supportedChristoph Hellwig3-26/+2
This function is largely identical to the generic version used everywhere else. Replace it with the generic version. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove dma_nommu_get_required_maskChristoph Hellwig3-15/+2
This function is identical to the generic dma_direct_get_required_mask, except that the generic version also takes the bus_dma_mask account, which could lead to incorrect results in the powerpc version. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove dma_nommu_mmap_coherentChristoph Hellwig7-28/+6
The coherent cache version of this function already is functionally identicall to the default version, and by defining the arch_dma_coherent_to_pfn hook the same is ture for the noncoherent version as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: use phys_to_dma instead of get_dma_offsetChristoph Hellwig1-5/+5
Use the standard portable helper instead of the powerpc specific one, which is about to go away. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18dma-mapping, powerpc: simplify the arch dma_set_mask overrideChristoph Hellwig9-24/+26
Instead of letting the architecture supply all of dma_set_mask just give it an additional hook selected by Kconfig. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: fix an off-by-one in dma_capableChristoph Hellwig1-6/+2
We need to compare the last byte in the dma range and not the one after it for the bus_dma_mask, just like we do for the regular dma_mask. Fix this cleanly by merging the two comparisms into one. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove max_direct_dma_addrChristoph Hellwig5-31/+6
The max_direct_dma_addr duplicates the bus_dma_mask field in struct device. Use the generic field instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: move pci_dma_dev_setup_swiotlb to fsl_pci.cChristoph Hellwig3-13/+9
pci_dma_dev_setup_swiotlb is only used by the fsl_pci code, and closely related to it, so fsl_pci.c seems like a better place for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove get_pci_dma_opsChristoph Hellwig3-17/+8
This function is only used by the Cell iommu code, which can keep track if it is using the iommu internally just as good. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: remove the iommu fallback for coherent allocationsChristoph Hellwig2-70/+2
All iommu capable platforms now always use the iommu code with the internal bypass, so there is not need for this magic anymore. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/pci: remove the dma_set_mask pci_controller ops methodsChristoph Hellwig2-9/+0
Unused now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: stop overriding dma_get_required_maskChristoph Hellwig6-38/+0
The ppc_md and pci_controller_ops methods are unused now and can be removed. The dma_nommu implementation is generic to the generic one except for using max_pfn instead of calling into the memblock API, and all other dma_map_ops instances implement a method of their own. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/powernv: use the generic iommu bypass codeChristoph Hellwig1-70/+25
Use the generic iommu bypass code instead of overriding set_dma_mask. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/powernv: remove pnv_npu_dma_set_maskChristoph Hellwig1-9/+0
These devices are not PCIe devices and do not have associated dma map ops, so this is just dead code. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/powernv: remove pnv_pci_ioda_pe_single_vendorChristoph Hellwig1-26/+2
This function is completely bogus - the fact that two PCIe devices come from the same vendor has absolutely nothing to say about the DMA capabilities and characteristics. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dart: use the generic iommu bypass codeChristoph Hellwig1-30/+17
Use the generic iommu bypass code instead of overriding set_dma_mask. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dart: remove dead cleanup code in iommu_init_early_dartChristoph Hellwig1-10/+1
If dart_init failed we didn't have a chance to setup dma or controller ops yet, so there is no point in resetting them. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/cell: use the generic iommu bypass codeChristoph Hellwig4-135/+20
This gets rid of a lot of clumsy code and finally allows us to mark dma_iommu_ops const. Includes fixes from Michael Ellerman. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/cell: move dma direct window setup out of dma_configureChristoph Hellwig1-9/+15
Configure the dma settings at device setup time, and stop playing games with get_pci_dma_ops. This prepares for using the common dma_configure code later on. Includes fixes from Michael Ellerman. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/pseries: use the generic iommu bypass codeChristoph Hellwig1-73/+27
Use the generic iommu bypass code instead of overriding set_dma_mask. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/pseries: unwind dma_get_required_mask_pSeriesLP a bitChristoph Hellwig1-1/+1
Call dma_get_required_mask_pSeriesLP directly instead of dma_iommu_ops to simply the code a bit. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: handle iommu bypass in dma_iommu_opsChristoph Hellwig5-17/+87
Add a new iommu_bypass flag to struct dev_archdata so that the dma_iommu implementation can handle the direct mapping transparently instead of switiching ops around. Setting of this flag is controlled by new pci_controller_ops method. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18powerpc/dma: untangle vio_dma_mapping_ops from dma_iommu_opsChristoph Hellwig3-52/+38
vio_dma_mapping_ops currently does a lot of indirect calls through dma_iommu_ops, which not only make the code harder to follow but are also expensive in the post-spectre world. Unwind the indirect calls by calling the ppc_iommu_* or iommu_* APIs directly applicable, or just use the dma_iommu_* methods directly where we can. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18dma-direct: we might need GFP_DMA for 32-bit dma masksChristoph Hellwig1-2/+1
If there is no ZONE_DMA32 we might need GFP_DMA to be able to allocate memory that satisfies a 32-bit DMA mask. Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-18net: pasemi: set a 64-bit DMA mask on the DMA deviceChristoph Hellwig1-0/+1
The pasemi driver never set a DMA mask, and given that the powerpc DMA mapping routines never check it this worked ok so far. But the generic dma-direct code which I plan to switch on for powerpc checks the DMA mask and fails unsupported mapping requests, so we need to make sure the proper 64-bit mask is set. Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-17powerpc/64s: Fix possible corruption on big endian due to pgd/pud_present()Michael Ellerman1-2/+2
In v4.20 we changed our pgd/pud_present() to check for _PAGE_PRESENT rather than just checking that the value is non-zero, e.g.: static inline int pgd_present(pgd_t pgd) { - return !pgd_none(pgd); + return (pgd_raw(pgd) & cpu_to_be64(_PAGE_PRESENT)); } Unfortunately this is broken on big endian, as the result of the bitwise & is truncated to int, which is always zero because _PAGE_PRESENT is 0x8000000000000000ul. This means pgd_present() and pud_present() are always false at compile time, and the compiler elides the subsequent code. Remarkably with that bug present we are still able to boot and run with few noticeable effects. However under some work loads we are able to trigger a warning in the ext4 code: WARNING: CPU: 11 PID: 29593 at fs/ext4/inode.c:3927 .ext4_set_page_dirty+0x70/0xb0 CPU: 11 PID: 29593 Comm: debugedit Not tainted 4.20.0-rc1 #1 ... NIP .ext4_set_page_dirty+0x70/0xb0 LR .set_page_dirty+0xa0/0x150 Call Trace: .set_page_dirty+0xa0/0x150 .unmap_page_range+0xbf0/0xe10 .unmap_vmas+0x84/0x130 .unmap_region+0xe8/0x190 .__do_munmap+0x2f0/0x510 .__vm_munmap+0x80/0x110 .__se_sys_munmap+0x14/0x30 system_call+0x5c/0x70 The fix is simple, we need to convert the result of the bitwise & to an int before returning it. Thanks to Erhard, Jan Kara and Aneesh for help with debugging. Fixes: da7ad366b497 ("powerpc/mm/book3s: Update pmd_present to look at _PAGE_PRESENT bit") Cc: stable@vger.kernel.org # v4.20+ Reported-by: Erhard F. <erhard_f@mailbox.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-07powerpc/powernv: Escalate reset when IODA reset failsOliver O'Halloran1-2/+5
The IODA reset is used to flush out any OS controlled state from the PHB. This reset can fail if a PHB fatal error has occurred in early boot, probably due to a because of a bad device. We already do a fundemental reset of the device in some cases, so this patch just adds a test to force a full reset if firmware reports an error when performing the IODA reset. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-07powerpc/ptrace: Mitigate potential Spectre v1Breno Leitao1-1/+7
'regno' is directly controlled by user space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. On PTRACE_SETREGS and PTRACE_GETREGS requests, user space passes the register number that would be read or written. This register number is called 'regno' which is part of the 'addr' syscall parameter. This 'regno' value is checked against the maximum pt_regs structure size, and then used to dereference it, which matches the initial part of a Spectre v1 (and Spectre v1.1) attack. The dereferenced value, then, is returned to userspace in the GETREGS case. This patch sanitizes 'regno' before using it to dereference pt_reg. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Signed-off-by: Breno Leitao <leitao@debian.org> Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-05powerpc/32: Include .branch_lt in data sectionJoel Stanley1-0/+1
When building a 32 bit powerpc kernel with Binutils 2.31.1 this warning is emitted: powerpc-linux-gnu-ld: warning: orphan section `.branch_lt' from `arch/powerpc/kernel/head_44x.o' being placed in section `.branch_lt' As of binutils commit 2d7ad24e8726 ("Support PLT16 relocs against local symbols")[1], 32 bit targets can produce .branch_lt sections in their output. Include these symbols in the .data section as the ppc64 kernel does. [1] https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commitdiff;h=2d7ad24e8726ba4c45c9e67be08223a146a837ce Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Alan Modra <amodra@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>