summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel
AgeCommit message (Collapse)AuthorFilesLines
2019-10-29powerpc/prom_init: Undo relocation before entering secure modeThiago Jung Bauermann2-1/+15
The ultravisor will do an integrity check of the kernel image but we relocated it so the check will fail. Restore the original image by relocating it back to the kernel virtual base address. This works because during build vmlinux is linked with an expected virtual runtime address of KERNELBASE. Fixes: 6a9c930bd775 ("powerpc/prom_init: Add the ESM call to prom_init") Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Tested-by: Michael Anderson <andmike@linux.ibm.com> [mpe: Add IS_ENABLED() to fix the CONFIG_RELOCATABLE=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911163433.12822-1-bauerman@linux.ibm.com
2019-09-27powerpc/eeh: Fix eeh eeh_debugfs_break_device() with SRIOV devicesOliver O'Halloran1-2/+2
s/CONFIG_IOV/CONFIG_PCI_IOV/ Whoops. Fixes: bd6461cc7b3c ("powerpc/eeh: Add a eeh_dev_break debugfs interface") Signed-off-by: Oliver O'Halloran <oohall@gmail.com> [mpe: Fixup the #endif comment as well] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190926122502.14826-1-oohall@gmail.com
2019-09-24powerpc/mm: Fixup tlbie vs mtpidr/mtlpidr ordering issue on POWER9Aneesh Kumar K.V1-0/+2
On POWER9, under some circumstances, a broadcast TLB invalidation will fail to invalidate the ERAT cache on some threads when there are parallel mtpidr/mtlpidr happening on other threads of the same core. This can cause stores to continue to go to a page after it's unmapped. The workaround is to force an ERAT flush using PID=0 or LPID=0 tlbie flush. This additional TLB flush will cause the ERAT cache invalidation. Since we are using PID=0 or LPID=0, we don't get filtered out by the TLB snoop filtering logic. We need to still follow this up with another tlbie to take care of store vs tlbie ordering issue explained in commit: a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9"). The presence of ERAT cache implies we can still get new stores and they may miss store queue marking flush. Cc: stable@vger.kernel.org Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190924035254.24612-3-aneesh.kumar@linux.ibm.com
2019-09-24powerpc/book3s64/radix: Rename CPU_FTR_P9_TLBIE_BUG feature flagAneesh Kumar K.V1-3/+3
Rename the #define to indicate this is related to store vs tlbie ordering issue. In the next patch, we will be adding another feature flag that is used to handles ERAT flush vs tlbie ordering issue. Fixes: a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190924035254.24612-2-aneesh.kumar@linux.ibm.com
2019-09-24powerpc/book3s64/mm: Don't do tlbie fixup for some hardware revisionsAneesh Kumar K.V1-2/+28
The store ordering vs tlbie issue mentioned in commit a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9") is fixed for Nimbus 2.3 and Cumulus 1.3 revisions. We don't need to apply the fixup if we are running on them We can only do this on PowerNV. On pseries guest with KVM we still don't support redoing the feature fixup after migration. So we should be enabling all the workarounds needed, because whe can possibly migrate between DD 2.3 and DD 2.2 Fixes: a5d4b5891c2f ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190924035254.24612-1-aneesh.kumar@linux.ibm.com
2019-09-24KVM: PPC: Book3S HV: use smp_mb() when setting/clearing host_ipi flagMichael Roth1-3/+3
On a 2-socket Power9 system with 32 cores/128 threads (SMT4) and 1TB of memory running the following guest configs: guest A: - 224GB of memory - 56 VCPUs (sockets=1,cores=28,threads=2), where: VCPUs 0-1 are pinned to CPUs 0-3, VCPUs 2-3 are pinned to CPUs 4-7, ... VCPUs 54-55 are pinned to CPUs 108-111 guest B: - 4GB of memory - 4 VCPUs (sockets=1,cores=4,threads=1) with the following workloads (with KSM and THP enabled in all): guest A: stress --cpu 40 --io 20 --vm 20 --vm-bytes 512M guest B: stress --cpu 4 --io 4 --vm 4 --vm-bytes 512M host: stress --cpu 4 --io 4 --vm 2 --vm-bytes 256M the below soft-lockup traces were observed after an hour or so and persisted until the host was reset (this was found to be reliably reproducible for this configuration, for kernels 4.15, 4.18, 5.0, and 5.3-rc5): [ 1253.183290] rcu: INFO: rcu_sched self-detected stall on CPU [ 1253.183319] rcu: 124-....: (5250 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=1941 [ 1256.287426] watchdog: BUG: soft lockup - CPU#105 stuck for 23s! [CPU 52/KVM:19709] [ 1264.075773] watchdog: BUG: soft lockup - CPU#24 stuck for 23s! [worker:19913] [ 1264.079769] watchdog: BUG: soft lockup - CPU#31 stuck for 23s! [worker:20331] [ 1264.095770] watchdog: BUG: soft lockup - CPU#45 stuck for 23s! [worker:20338] [ 1264.131773] watchdog: BUG: soft lockup - CPU#64 stuck for 23s! [avocado:19525] [ 1280.408480] watchdog: BUG: soft lockup - CPU#124 stuck for 22s! [ksmd:791] [ 1316.198012] rcu: INFO: rcu_sched self-detected stall on CPU [ 1316.198032] rcu: 124-....: (21003 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=8243 [ 1340.411024] watchdog: BUG: soft lockup - CPU#124 stuck for 22s! [ksmd:791] [ 1379.212609] rcu: INFO: rcu_sched self-detected stall on CPU [ 1379.212629] rcu: 124-....: (36756 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=14714 [ 1404.413615] watchdog: BUG: soft lockup - CPU#124 stuck for 22s! [ksmd:791] [ 1442.227095] rcu: INFO: rcu_sched self-detected stall on CPU [ 1442.227115] rcu: 124-....: (52509 ticks this GP) idle=10a/1/0x4000000000000002 softirq=5408/5408 fqs=21403 [ 1455.111787] INFO: task worker:19907 blocked for more than 120 seconds. [ 1455.111822] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.111833] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.111884] INFO: task worker:19908 blocked for more than 120 seconds. [ 1455.111905] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.111925] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.111966] INFO: task worker:20328 blocked for more than 120 seconds. [ 1455.111986] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.111998] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112048] INFO: task worker:20330 blocked for more than 120 seconds. [ 1455.112068] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112097] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112138] INFO: task worker:20332 blocked for more than 120 seconds. [ 1455.112159] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112179] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112210] INFO: task worker:20333 blocked for more than 120 seconds. [ 1455.112231] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112242] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112282] INFO: task worker:20335 blocked for more than 120 seconds. [ 1455.112303] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 [ 1455.112332] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1455.112372] INFO: task worker:20336 blocked for more than 120 seconds. [ 1455.112392] Tainted: G L 5.3.0-rc5-mdr-vanilla+ #1 CPUs 45, 24, and 124 are stuck on spin locks, likely held by CPUs 105 and 31. CPUs 105 and 31 are stuck in smp_call_function_many(), waiting on target CPU 42. For instance: # CPU 105 registers (via xmon) R00 = c00000000020b20c R16 = 00007d1bcd800000 R01 = c00000363eaa7970 R17 = 0000000000000001 R02 = c0000000019b3a00 R18 = 000000000000006b R03 = 000000000000002a R19 = 00007d537d7aecf0 R04 = 000000000000002a R20 = 60000000000000e0 R05 = 000000000000002a R21 = 0801000000000080 R06 = c0002073fb0caa08 R22 = 0000000000000d60 R07 = c0000000019ddd78 R23 = 0000000000000001 R08 = 000000000000002a R24 = c00000000147a700 R09 = 0000000000000001 R25 = c0002073fb0ca908 R10 = c000008ffeb4e660 R26 = 0000000000000000 R11 = c0002073fb0ca900 R27 = c0000000019e2464 R12 = c000000000050790 R28 = c0000000000812b0 R13 = c000207fff623e00 R29 = c0002073fb0ca808 R14 = 00007d1bbee00000 R30 = c0002073fb0ca800 R15 = 00007d1bcd600000 R31 = 0000000000000800 pc = c00000000020b260 smp_call_function_many+0x3d0/0x460 cfar= c00000000020b270 smp_call_function_many+0x3e0/0x460 lr = c00000000020b20c smp_call_function_many+0x37c/0x460 msr = 900000010288b033 cr = 44024824 ctr = c000000000050790 xer = 0000000000000000 trap = 100 CPU 42 is running normally, doing VCPU work: # CPU 42 stack trace (via xmon) [link register ] c00800001be17188 kvmppc_book3s_radix_page_fault+0x90/0x2b0 [kvm_hv] [c000008ed3343820] c000008ed3343850 (unreliable) [c000008ed33438d0] c00800001be11b6c kvmppc_book3s_hv_page_fault+0x264/0xe30 [kvm_hv] [c000008ed33439d0] c00800001be0d7b4 kvmppc_vcpu_run_hv+0x8dc/0xb50 [kvm_hv] [c000008ed3343ae0] c00800001c10891c kvmppc_vcpu_run+0x34/0x48 [kvm] [c000008ed3343b00] c00800001c10475c kvm_arch_vcpu_ioctl_run+0x244/0x420 [kvm] [c000008ed3343b90] c00800001c0f5a78 kvm_vcpu_ioctl+0x470/0x7c8 [kvm] [c000008ed3343d00] c000000000475450 do_vfs_ioctl+0xe0/0xc70 [c000008ed3343db0] c0000000004760e4 ksys_ioctl+0x104/0x120 [c000008ed3343e00] c000000000476128 sys_ioctl+0x28/0x80 [c000008ed3343e20] c00000000000b388 system_call+0x5c/0x70 --- Exception: c00 (System Call) at 00007d545cfd7694 SP (7d53ff7edf50) is in userspace It was subsequently found that ipi_message[PPC_MSG_CALL_FUNCTION] was set for CPU 42 by at least 1 of the CPUs waiting in smp_call_function_many(), but somehow the corresponding call_single_queue entries were never processed by CPU 42, causing the callers to spin in csd_lock_wait() indefinitely. Nick Piggin suggested something similar to the following sequence as a possible explanation (interleaving of CALL_FUNCTION/RESCHEDULE IPI messages seems to be most common, but any mix of CALL_FUNCTION and !CALL_FUNCTION messages could trigger it): CPU X: smp_muxed_ipi_set_message(): X: smp_mb() X: message[RESCHEDULE] = 1 X: doorbell_global_ipi(42): X: kvmppc_set_host_ipi(42, 1) X: ppc_msgsnd_sync()/smp_mb() X: ppc_msgsnd() -> 42 42: doorbell_exception(): // from CPU X 42: ppc_msgsync() 105: smp_muxed_ipi_set_message(): 105: smb_mb() // STORE DEFERRED DUE TO RE-ORDERING --105: message[CALL_FUNCTION] = 1 | 105: doorbell_global_ipi(42): | 105: kvmppc_set_host_ipi(42, 1) | 42: kvmppc_set_host_ipi(42, 0) | 42: smp_ipi_demux_relaxed() | 42: // returns to executing guest | // RE-ORDERED STORE COMPLETES ->105: message[CALL_FUNCTION] = 1 105: ppc_msgsnd_sync()/smp_mb() 105: ppc_msgsnd() -> 42 42: local_paca->kvm_hstate.host_ipi == 0 // IPI ignored 105: // hangs waiting on 42 to process messages/call_single_queue This can be prevented with an smp_mb() at the beginning of kvmppc_set_host_ipi(), such that stores to message[<type>] (or other state indicated by the host_ipi flag) are ordered vs. the store to to host_ipi. However, doing so might still allow for the following scenario (not yet observed): CPU X: smp_muxed_ipi_set_message(): X: smp_mb() X: message[RESCHEDULE] = 1 X: doorbell_global_ipi(42): X: kvmppc_set_host_ipi(42, 1) X: ppc_msgsnd_sync()/smp_mb() X: ppc_msgsnd() -> 42 42: doorbell_exception(): // from CPU X 42: ppc_msgsync() // STORE DEFERRED DUE TO RE-ORDERING -- 42: kvmppc_set_host_ipi(42, 0) | 42: smp_ipi_demux_relaxed() | 105: smp_muxed_ipi_set_message(): | 105: smb_mb() | 105: message[CALL_FUNCTION] = 1 | 105: doorbell_global_ipi(42): | 105: kvmppc_set_host_ipi(42, 1) | // RE-ORDERED STORE COMPLETES -> 42: kvmppc_set_host_ipi(42, 0) 42: // returns to executing guest 105: ppc_msgsnd_sync()/smp_mb() 105: ppc_msgsnd() -> 42 42: local_paca->kvm_hstate.host_ipi == 0 // IPI ignored 105: // hangs waiting on 42 to process messages/call_single_queue Fixing this scenario would require an smp_mb() *after* clearing host_ipi flag in kvmppc_set_host_ipi() to order the store vs. subsequent processing of IPI messages. To handle both cases, this patch splits kvmppc_set_host_ipi() into separate set/clear functions, where we execute smp_mb() prior to setting host_ipi flag, and after clearing host_ipi flag. These functions pair with each other to synchronize the sender and receiver sides. With that change in place the above workload ran for 20 hours without triggering any lock-ups. Fixes: 755563bc79c7 ("powerpc/powernv: Fixes for hypervisor doorbell handling") # v4.0 Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911223155.16045-1-mdroth@linux.vnet.ibm.com
2019-09-21powerpc/64s: Set reserved PCR bitsJordan Niethe2-1/+8
Currently the reserved bits of the Processor Compatibility Register (PCR) are cleared as per the Programming Note in Section 1.3.3 of version 3.0B of the Power ISA. This causes all new architecture features to be made available when running on newer processors with new architecture features added to the PCR as bits must be set to disable a given feature. For example to disable new features added as part of Version 2.07 of the ISA the corresponding bit in the PCR needs to be set. As new processor features generally require explicit kernel support they should be disabled until such support is implemented. Therefore kernels should set all unknown/reserved bits in the PCR such that any new architecture features which the kernel does not currently know about get disabled. An update is planned to the ISA to clarify that the PCR is an exception to the Programming Note on reserved bits in Section 1.3.3. Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190917004605.22471-2-alistair@popple.id.au
2019-09-20Merge tag 'powerpc-5.4-1' of ↵Linus Torvalds55-2159/+2715
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "This is a bit late, partly due to me travelling, and partly due to a power outage knocking out some of my test systems *while* I was travelling. - Initial support for running on a system with an Ultravisor, which is software that runs below the hypervisor and protects guests against some attacks by the hypervisor. - Support for building the kernel to run as a "Secure Virtual Machine", ie. as a guest capable of running on a system with an Ultravisor. - Some changes to our DMA code on bare metal, to allow devices with medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space. - Support for firmware assisted crash dumps on bare metal (powernv). - Two series fixing bugs in and refactoring our PCI EEH code. - A large series refactoring our exception entry code to use gas macros, both to make it more readable and also enable some future optimisations. As well as many cleanups and other minor features & fixups. Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar, Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde" * tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits) powerpc/mm/mce: Keep irqs disabled during lockless page table walk powerpc: Use ftrace_graph_ret_addr() when unwinding powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR ftrace: Look up the address of return_to_handler() using helpers powerpc: dump kernel log before carrying out fadump or kdump docs: powerpc: Add missing documentation reference powerpc/xmon: Fix output of XIVE IPI powerpc/xmon: Improve output of XIVE interrupts powerpc/mm/radix: remove useless kernel messages powerpc/fadump: support holes in kernel boot memory area powerpc/fadump: remove RMA_START and RMA_END macros powerpc/fadump: update documentation about option to release opalcore powerpc/fadump: consider f/w load area powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel powerpc/fadump: improve how crashed kernel's memory is reserved powerpc/fadump: consider reserved ranges while releasing memory powerpc/fadump: make crash memory ranges array allocation generic ...
2019-09-20Merge tag 'kbuild-v5.4' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - add modpost warn exported symbols marked as 'static' because 'static' and EXPORT_SYMBOL is an odd combination - break the build early if gold linker is used - optimize the Bison rule to produce .c and .h files by a single pattern rule - handle PREEMPT_RT in the module vermagic and UTS_VERSION - warn CONFIG options leaked to the user-space except existing ones - make single targets work properly - rebuild modules when module linker scripts are updated - split the module final link stage into scripts/Makefile.modfinal - fix the missed error code in merge_config.sh - improve the error message displayed on the attempt of the O= build in unclean source tree - remove 'clean-dirs' syntax - disable -Wimplicit-fallthrough warning for Clang - add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC - remove ARCH_{CPP,A,C}FLAGS variables - add $(BASH) to run bash scripts - change *CFLAGS_<basetarget>.o to take the relative path to $(obj) instead of the basename - stop suppressing Clang's -Wunused-function warnings when W=1 - fix linux/export.h to avoid genksyms calculating CRC of trimmed exported symbols - misc cleanups * tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits) genksyms: convert to SPDX License Identifier for lex.l and parse.y modpost: use __section in the output to *.mod.c modpost: use MODULE_INFO() for __module_depends export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols export.h: remove defined(__KERNEL__), which is no longer needed kbuild: allow Clang to find unused static inline functions for W=1 build kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN kbuild: refactor scripts/Makefile.extrawarn merge_config.sh: ignore unwanted grep errors kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj) modpost: add NOFAIL to strndup modpost: add guid_t type definition kbuild: add $(BASH) to run scripts with bash-extension kbuild: remove ARCH_{CPP,A,C}FLAGS kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC kbuild: Do not enable -Wimplicit-fallthrough for clang for now kbuild: clean up subdir-ymn calculation in Makefile.clean kbuild: remove unneeded '+' marker from cmd_clean kbuild: remove clean-dirs syntax kbuild: check clean srctree even earlier ...
2019-09-19Merge tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-0/+2
Pull dma-mapping updates from Christoph Hellwig: - add dma-mapping and block layer helpers to take care of IOMMU merging for mmc plus subsequent fixups (Yoshihiro Shimoda) - rework handling of the pgprot bits for remapping (me) - take care of the dma direct infrastructure for swiotlb-xen (me) - improve the dma noncoherent remapping infrastructure (me) - better defaults for ->mmap, ->get_sgtable and ->get_required_mask (me) - cleanup mmaping of coherent DMA allocations (me) - various misc cleanups (Andy Shevchenko, me) * tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping: (41 commits) mmc: renesas_sdhi_internal_dmac: Add MMC_CAP2_MERGE_CAPABLE mmc: queue: Fix bigger segments usage arm64: use asm-generic/dma-mapping.h swiotlb-xen: merge xen_unmap_single into xen_swiotlb_unmap_page swiotlb-xen: simplify cache maintainance swiotlb-xen: use the same foreign page check everywhere swiotlb-xen: remove xen_swiotlb_dma_mmap and xen_swiotlb_dma_get_sgtable xen: remove the exports for xen_{create,destroy}_contiguous_region xen/arm: remove xen_dma_ops xen/arm: simplify dma_cache_maint xen/arm: use dev_is_dma_coherent xen/arm: consolidate page-coherent.h xen/arm: use dma-noncoherent.h calls for xen-swiotlb cache maintainance arm: remove wrappers for the generic dma remap helpers dma-mapping: introduce a dma_common_find_pages helper dma-mapping: always use VM_DMA_COHERENT for generic DMA remap vmalloc: lift the arm flag for coherent mappings to common code dma-mapping: provide a better default ->get_required_mask dma-mapping: remove the dma_declare_coherent_memory export remoteproc: don't allow modular build ...
2019-09-19powerpc/mm/mce: Keep irqs disabled during lockless page table walkAneesh Kumar K.V1-8/+12
__find_linux_mm_pte() returns a page table entry pointer after walking the page table without holding locks. To make it safe against a THP split and/or collapse, we disable interrupts around the lockless page table walk. However we need to keep interrupts disabled as long as we use the page table entry pointer that is returned. Fix addr_to_pfn() to do that. Fixes: ba41e1e1ccb9 ("powerpc/mce: Hookup derror (load/store) UE errors") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [mpe: Rearrange code slightly and tweak change log wording] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190918145328.28602-1-aneesh.kumar@linux.ibm.com
2019-09-18Merge tag 'usb-5.4-rc1' of ↵Linus Torvalds1-6/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB updates from Greg KH: "Here is the big set of USB patches for 5.4-rc1. Two major chunks of code are moving out of the tree and into the staging directory, uwb and wusb (wireless USB support), because there are no devices that actually use this protocol anymore, and what we have today probably doesn't work at all given that the maintainers left many many years ago. So move it to staging where it will be removed in a few releases if no one screams. Other than that, lots of little things. The usual gadget and xhci and usb serial driver updates, along with a bunch of sysfs file cleanups due to the driver core changes to support that. Nothing really major, just constant forward progress. All of these have been in linux-next for a while with no reported issues" * tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (159 commits) USB: usbcore: Fix slab-out-of-bounds bug during device reset usb: cdns3: Remove redundant dev_err call in cdns3_probe() USB: rio500: Fix lockdep violation USB: rio500: simplify locking usb: mtu3: register a USB Role Switch for dual role mode usb: common: add USB GPIO based connection detection driver usb: common: create Kconfig file usb: roles: get usb-role-switch from parent usb: roles: Add fwnode_usb_role_switch_get() function device connection: Add fwnode_connection_find_match() usb: roles: Introduce stubs for the exiting functions in role.h dt-bindings: usb: mtu3: add properties about USB Role Switch dt-bindings: usb: add binding for USB GPIO based connection detection driver dt-bindings: connector: add optional properties for Type-B dt-binding: usb: add usb-role-switch property usbip: Implement SG support to vhci-hcd and stub driver usb: roles: intel: Enable static DRD mode for role switch xhci-ext-caps.c: Add property to disable Intel SW switch usb: dwc3: remove generic PHY calibrate() calls usb: core: phy: add support for PHY calibration ...
2019-09-18powerpc: Use ftrace_graph_ret_addr() when unwindingNaveen N. Rao1-13/+6
With support for HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, ftrace_graph_ret_addr() provides more robust unwinding when function graph is in use. Update show_stack() to use the same. With dump_stack() added to sysrq_sysctl_handler(), before this patch: root@(none):/sys/kernel/debug/tracing# cat /proc/sys/kernel/sysrq CPU: 0 PID: 218 Comm: cat Not tainted 5.3.0-rc7-00868-g8453ad4a078c-dirty #20 Call Trace: [c0000000d1e13c30] [c00000000006ab98] return_to_handler+0x0/0x40 (dump_stack+0xe8/0x164) (unreliable) [c0000000d1e13c80] [c000000000145680] sysrq_sysctl_handler+0x48/0xb8 [c0000000d1e13cd0] [c00000000006ab98] return_to_handler+0x0/0x40 (proc_sys_call_handler+0x274/0x2a0) [c0000000d1e13d60] [c00000000006ab98] return_to_handler+0x0/0x40 (return_to_handler+0x0/0x40) [c0000000d1e13d80] [c00000000006ab98] return_to_handler+0x0/0x40 (__vfs_read+0x3c/0x70) [c0000000d1e13dd0] [c00000000006ab98] return_to_handler+0x0/0x40 (vfs_read+0xb8/0x1b0) [c0000000d1e13e20] [c00000000006ab98] return_to_handler+0x0/0x40 (ksys_read+0x7c/0x140) After this patch: Call Trace: [c0000000d1e33c30] [c00000000006ab58] return_to_handler+0x0/0x40 (dump_stack+0xe8/0x164) (unreliable) [c0000000d1e33c80] [c000000000145680] sysrq_sysctl_handler+0x48/0xb8 [c0000000d1e33cd0] [c00000000006ab58] return_to_handler+0x0/0x40 (proc_sys_call_handler+0x274/0x2a0) [c0000000d1e33d60] [c00000000006ab58] return_to_handler+0x0/0x40 (__vfs_read+0x3c/0x70) [c0000000d1e33d80] [c00000000006ab58] return_to_handler+0x0/0x40 (vfs_read+0xb8/0x1b0) [c0000000d1e33dd0] [c00000000006ab58] return_to_handler+0x0/0x40 (ksys_read+0x7c/0x140) [c0000000d1e33e20] [c00000000006ab58] return_to_handler+0x0/0x40 (system_call+0x5c/0x68) Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/dc89c9a887121342d9c7819482c3dabdece2a323.1567707399.git.naveen.n.rao@linux.vnet.ibm.com
2019-09-18powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTRNaveen N. Rao5-3/+7
This associates entries in the ftrace_ret_stack with corresponding stack frames, enabling more robust stack unwinding. Also update the only user of ftrace_graph_ret_addr() to pass the stack pointer. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/0224f2d0971b069c678e2ff678cfc2cd1e114cfe.1567707399.git.naveen.n.rao@linux.vnet.ibm.com
2019-09-18powerpc: dump kernel log before carrying out fadump or kdumpGanesh Goudar1-0/+1
Since commit 4388c9b3a6ee ("powerpc: Do not send system reset request through the oops path"), pstore dmesg file is not updated when dump is triggered from HMC. This commit modified system reset (sreset) handler to invoke fadump or kdump (if configured), without pushing dmesg to pstore. This leaves pstore to have old dmesg data which won't be much of a help if kdump fails to capture the dump. This patch fixes that by calling kmsg_dump() before heading to fadump ot kdump. Fixes: 4388c9b3a6ee ("powerpc: Do not send system reset request through the oops path") Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190904075949.15607-1-ganeshgr@linux.ibm.com
2019-09-16Merge branch 'parisc-5.4-1' of ↵Linus Torvalds1-540/+5
git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux Pull parisc updates from Helge Deller: - Make the powerpc implementation to read elf files available as a public kexec interface so it can be re-used on other architectures (Sven) - Implement kexec on parisc (Sven) - Add kprobes on ftrace on parisc (Sven) - Fix kernel crash with HSC-PCI cards based on card-mode Dino - Add assembly implementations for memset, strlen, strcpy, strncpy and strcat - Some cleanups, documentation updates, warning fixes, ... * 'parisc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (25 commits) parisc: Have git ignore generated real2.S and firmware.c parisc: Disable HP HSC-PCI Cards to prevent kernel crash parisc: add support for kexec_file_load() syscall parisc: wire up kexec_file_load syscall parisc: add kexec syscall support parisc: add __pdc_cpu_rendezvous() kprobes/parisc: remove arch_kprobe_on_func_entry() kexec_elf: support 32 bit ELF files kexec_elf: remove unused variable in kexec_elf_load() kexec_elf: remove Elf_Rel macro kexec_elf: remove PURGATORY_STACK_SIZE kexec_elf: remove parsing of section headers kexec_elf: change order of elf_*_to_cpu() functions kexec: add KEXEC_ELF parisc: Save some bytes in dino driver parisc: Drop comments which are already in pci.h parisc: Convert eisa_enumerator to use pr_cont() parisc: Avoid warning when loading hppb driver parisc: speed up flush_tlb_all_local with qemu parisc: Add ALTERNATIVE_CODE() and ALT_COND_RUN_ON_QEMU ...
2019-09-14powerpc/fadump: support holes in kernel boot memory areaHari Bathini1-29/+162
With support to copy multiple kernel boot memory regions owing to copy size limitation, also handle holes in the memory area to be preserved. Support as many as 128 kernel boot memory regions. This allows having an adequate FADump capture kernel size for different scenarios. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821385448.5656.6124791213910877759.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: remove RMA_START and RMA_END macrosHari Bathini1-15/+17
RMA_START is defined as '0' and there is even a BUILD_BUG_ON() to make sure it is never anything else. Remove this macro and use '0' instead as code change is needed anyway when it has to be something else. Also, remove unused RMA_END macro. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821384096.5656.15026984053970204652.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: consider f/w load areaHari Bathini1-4/+12
OPAL loads kernel & initrd at 512MB offset (256MB size), also exported as ibm,opal/dump/fw-load-area. So, if boot memory size of FADump is less than 768MB, kernel memory to be exported as '/proc/vmcore' would be overwritten by f/w while loading kernel & initrd. To avoid such a scenario, enforce a minimum boot memory size of 768MB on OPAL platform and skip using FADump if a newer F/W version loads kernel & initrd above 768MB. Also, irrespective of RMA size, set the minimum boot memory size expected on pseries platform at 320MB. This is to avoid inflating the minimum memory requirements on systems with 512M/1024M RMA size. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821381414.5656.1592867278535469652.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: add support to preserve crash data on FADUMP disabled kernelHari Bathini3-8/+44
Add a new kernel config option, CONFIG_PRESERVE_FA_DUMP that ensures that crash data, from previously crash'ed kernel, is preserved. This helps in cases where FADump is not enabled but the subsequent memory preserving kernel boot is likely to process this crash data. One typical usecase for this config option is petitboot kernel. As OPAL allows registering address with it in the first kernel and retrieving it after MPIPL, use it to store the top of boot memory. A kernel that intends to preserve crash data retrieves it and avoids using memory beyond this address. Move arch_reserved_kernel_pages() function as it is needed for both FA_DUMP and PRESERVE_FA_DUMP configurations. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821375751.5656.11459483669542541602.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: improve how crashed kernel's memory is reservedHari Bathini1-24/+29
The size parameter to fadump_reserve_crash_area() function is not needed as all the memory above boot memory size must be preserved anyway. Update the function by dropping this redundant parameter. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821374440.5656.2945512543806951766.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: consider reserved ranges while releasing memoryHari Bathini1-21/+146
Commit 0962e8004e97 ("powerpc/prom: Scan reserved-ranges node for memory reservations") enabled support to parse 'reserved-ranges' DT node to reserve kernel memory falling in these ranges for firmware purposes. Along with the preserved area memory, ensure memory in reserved ranges is not overlapped with memory released by capture kernel aftering saving vmcore. Also, fix the off-by-one error in fadump_release_reserved_area function while releasing memory. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821371358.5656.6061214942558818661.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: make crash memory ranges array allocation genericHari Bathini1-53/+60
Make allocate_crash_memory_ranges() and free_crash_memory_ranges() functions generic to reuse them for memory management of all types of dynamic memory range arrays. This change helps in memory management of reserved ranges array to be added later. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821369863.5656.4375667005352155892.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: make use of memblock's bottom up allocation modeHari Bathini1-14/+12
Earlier, memblock_find_in_range() was not used to find the memory to be reserved for FADump as bottom up allocation mode was not supported. But since commit 79442ed189acb8b ("mm/memblock.c: introduce bottom-up allocation mode") bottom up allocation mode is supported for memblock. So, use it to find the memory to be reserved for FADump. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821364211.5656.14336025460336135194.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: handle invalidation of crashdump and re-registraionHari Bathini1-1/+7
Make OPAL call to indicate that the dump is processed and the metadata area in OPAL can be cleared/released. Also, setup/initialize FADump for re-registration. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821356046.5656.12270927048195494911.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: reset metadata address during clean upHari Bathini1-0/+6
During kexec boot, metadata address needs to be reset to avoid running into errors interpreting stale metadata address, in case the kexec'ed kernel crashes before metadata address could be setup again. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821346629.5656.10783321582005237813.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: register kernel metadata address with opalHari Bathini1-3/+20
OPAL allows registering address with it in the first kernel and retrieving it after MPIPL. Setup kernel metadata and register its address with OPAL to use it for processing the crash dump. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821345011.5656.13567765019032928471.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: improve fadump_reserve_mem()Hari Bathini1-23/+25
Some code clean-up like using minimal assignments and updating printk messages. Also, add an 'error_out' label for handling error cleanup at one place. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821343485.5656.10202857091553646948.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: add fadump support on powernvHari Bathini1-3/+12
Add basic callback functions for FADump on PowerNV platform. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821342072.5656.4346362203141486452.stgit@hbathini.in.ibm.com
2019-09-14pseries/fadump: move out platform specific support from generic codeHari Bathini1-315/+14
Move code that supports processing the crash'ed kernel's memory preserved by firmware to platform specific callback functions. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821337690.5656.13050665924800177744.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: release all the memory above boot memory sizeHari Bathini1-24/+10
Except for Reserved dump area (see Documentation/powerpc/firmware- assisted-dump.rst) which is permanent reserved, all memory above boot memory size, where boot memory size is the memory required for the kernel to boot successfully when booted with restricted memory (memory for capture kernel), is released when the dump is invalidated. Make this a bit more explicit in the code. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821336092.5656.1079046285366041687.stgit@hbathini.in.ibm.com
2019-09-14pseries/fadump: define RTAS register/un-register callback functionsHari Bathini1-150/+15
Move platform specific register/un-register code, the RTAS calls, to register/un-register callback functions. This would also mean moving code that initializes and prints the platform specific FADump data. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821332856.5656.16380417702046411631.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: introduce callbacks for platform specific operationsHari Bathini1-44/+1
Introduce callback functions for platform specific operations like register, unregister, invalidate & such. Also, define place-holders for the same on pSeries platform. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821330286.5656.15538934400074110770.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: move rtas specific definitions to platform codeHari Bathini1-47/+49
Currently, FADump is only supported on pSeries but that is going to change soon with FADump support being added on PowerNV platform. So, move rtas specific definitions to platform code to allow FADump to have multiple platforms support. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821328494.5656.16219929140866195511.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: use helper functions to reserve/release cpu notes bufferHari Bathini1-15/+6
Use helper functions to simplify memory allocation, pinning down and freeing the memory used for CPU notes buffer. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821323555.5656.2486038022572739622.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: declare helper functions in internal header fileHari Bathini1-8/+8
Declare helper functions, that can be reused by multiple platforms, in the internal header file. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821320487.5656.2660730464212209984.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: add helper functionsHari Bathini1-61/+66
Add helper functions to setup & free CPU notes buffer and to find if a given memory area is contiguous. Also, use boolean as return type for the function that finds if boot memory area is contiguous. While at it, save the virtual address of CPU notes buffer instead of physical address as virtual address is used often. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821318971.5656.9281936950510635858.stgit@hbathini.in.ibm.com
2019-09-14powerpc/fadump: move internal macros/definitions to a new headerHari Bathini1-0/+1
Though asm/fadump.h is meant to be used by other components dealing with FADump, it also has macros/definitions internal to FADump code. Move them to a new header file used within FADump code. This also makes way for refactoring platform specific FADump code. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/156821313134.5656.6597770626574392140.stgit@hbathini.in.ibm.com
2019-09-14powerpc: improve prom_init_check ruleMasahiro Yamada2-8/+7
This slightly improves the prom_init_check rule. [1] Avoid needless check Currently, prom_init_check.sh is invoked every time you run 'make' even if you have changed nothing in prom_init.c. With this commit, the script is re-run only when prom_init.o is recompiled. [2] Beautify the build log Currently, the O= build shows the absolute path to the script: CALL /abs/path/to/source/of/linux/arch/powerpc/kernel/prom_init_check.sh With this commit, it is always a relative path to the timestamp file: PROMCHK arch/powerpc/kernel/prom_init_check Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190912074037.13813-1-yamada.masahiro@socionext.com
2019-09-14powerpc/kvm: Add ifdefs around template codeMichael Ellerman1-0/+8
Some of the templates used for KVM patching are only used on certain platforms, but currently they are always built-in, fix that. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911115746.12433-4-mpe@ellerman.id.au
2019-09-14powerpc/kvm: Explicitly mark kvm guest code as __initMichael Ellerman1-17/+17
All the code in kvm.c can be marked __init. Most of it is already inlined into the initcall, but not all. So instead of relying on the inlining, mark it all as __init. This saves ~280 bytes of text for my configuration. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911115746.12433-3-mpe@ellerman.id.au
2019-09-14powerpc/kvm: Move kvm_tmp into .text, shrink to 64KMichael Ellerman2-19/+13
In some configurations of KVM, guests binary patch themselves to avoid/reduce trapping into the hypervisor. For some instructions this requires replacing one instruction with a sequence of instructions. For those cases we need to write the sequence of instructions somewhere and then patch the location of the original instruction to branch to the sequence. That requires that the location of the sequence be within 32MB of the original instruction. The current solution for this is that we create a 1MB array in BSS, write sequences into there, and then free the remainder of the array. This has a few problems: - it confuses kmemleak. - it confuses lockdep. - it requires mapping kvm_tmp executable, which can cause adjacent areas to also be mapped executable if we're using 16M pages for the linear mapping. - the 32MB limit can be exceeded if the kernel is big enough, especially with STRICT_KERNEL_RWX enabled, which then prevents the patching from working at all. We can fix all those problems by making kvm_tmp just a region of regular .text. However currently it's 1MB in size, and we don't want to waste 1MB of text. In practice however I only see ~30KB of kvm_tmp being used even for an allyes_config. So shrink kvm_tmp to 64K, which ought to be enough for everyone, and move it into .text. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190911115746.12433-1-mpe@ellerman.id.au
2019-09-14powerpc/eeh: Fix build with STACKTRACE=nMichael Ellerman2-1/+4
The build breaks when STACKTRACE=n, eg. skiroot_defconfig: arch/powerpc/kernel/eeh_event.c:124:23: error: implicit declaration of function 'stack_trace_save' Fix it with some ifdefs for now. Fixes: 25baf3d81614 ("powerpc/eeh: Defer printing stack trace") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-09-12powerpc/watchpoint: Disable watchpoint hit by larx/stcx instructionsRavi Bangoria1-16/+33
If watchpoint exception is generated by larx/stcx instructions, the reservation created by larx gets lost while handling exception, and thus stcx instruction always fails. Generally these instructions are used in a while(1) loop, for example spinlocks. And because stcx never succeeds, it loops forever and ultimately hangs the system. Note that ptrace anyway works in one-shot mode and thus for ptrace we don't change the behaviour. It's up to ptrace user to take care of this. Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190910131513.30499-1-ravi.bangoria@linux.ibm.com
2019-09-06kexec: add KEXEC_ELFSven Schnelle1-540/+5
Right now powerpc provides an implementation to read elf files with the kexec_file_load() syscall. Make that available as a public kexec interface so it can be re-used on other architectures. Signed-off-by: Sven Schnelle <svens@stackframe.org> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Helge Deller <deller@gmx.de>
2019-09-06Merge tag 'powerpc-5.3-5' of ↵Linus Torvalds1-17/+4
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "One fix for a boot hang on some Freescale machines when PREEMPT is enabled. Two CVE fixes for bugs in our handling of FP registers and transactional memory, both of which can result in corrupted FP state, or FP state leaking between processes. Thanks to: Chris Packham, Christophe Leroy, Gustavo Romero, Michael Neuling" * tag 'powerpc-5.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/tm: Fix restoring FP/VMX facility incorrectly on interrupts powerpc/tm: Fix FP/VMX unavailable exceptions inside a transaction powerpc/64e: Drop stale call to smp_processor_id() which hangs SMP startup
2019-09-05powerpc/eeh: Add a eeh_dev_break debugfs interfaceOliver O'Halloran1-1/+138
Add an interface to debugfs for generating an EEH event on a given device. This works by disabling memory accesses to and from the device by setting the PCI_COMMAND register (or the VF Memory Space Enable on the parent PF). This is a somewhat portable alternative to using the platform specific error injection mechanisms since those tend to be either hard to use, or straight up broken. For pseries the interfaces also requires the use of /dev/mem which is probably going to go away in a post-LOCKDOWN world (and it's a horrific hack to begin with) so moving to a kernel-provided interface makes sense and provides a sane, cross-platform interface for userspace so we can write more generic testing scripts. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-14-oohall@gmail.com
2019-09-05powerpc/eeh: Add debugfs interface to run an EEH checkOliver O'Halloran1-0/+61
Detecting an frozen EEH PE usually occurs when an MMIO load returns a 0xFFs response. When performing EEH testing using the EEH error injection feature available on some platforms there is no simple way to kick-off the kernel's recovery process since any accesses from userspace (usually /dev/mem) will bypass the MMIO helpers in the kernel which check if a 0xFF response is due to an EEH freeze or not. If a device contains a 0xFF byte in it's config space it's possible to trigger the recovery process via config space read from userspace, but this is not a reliable method. If a driver is bound to the device an in use it will frequently trigger the MMIO check, but this is also inconsistent. To solve these problems this patch adds a debugfs file called "eeh_dev_check" which accepts a <domain>:<bus>:<dev>.<fn> string and runs eeh_dev_check_failure() on it. This is the same check that's done when the kernel gets a 0xFF result from an config or MMIO read with the added benifit that it can be reliably triggered from userspace. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-13-oohall@gmail.com
2019-09-05powerpc/eeh: Set attention indicator while recoveringOliver O'Halloran1-0/+32
I am the RAS team. Hear me roar. Roar. On a more serious note, being able to locate failed devices can be helpful. Set the attention indicator if the slot supports it once we've determined the device is present and only clear it if the device is fully recovered. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-12-oohall@gmail.com
2019-09-05powerpc/eeh: Defer printing stack traceOliver O'Halloran3-26/+53
Currently we print a stack trace in the event handler to help with debugging EEH issues. In the case of suprise hot-unplug this is unneeded, so we want to prevent printing the stack trace unless we know it's due to an actual device error. To accomplish this, we can save a stack trace at the point of detection and only print it once the EEH recovery handler has determined the freeze was due to an actual error. Since the whole point of this is to prevent spurious EEH output we also move a few prints out of the detection thread, or mark them as pr_debug so anyone interested can get output from the eeh_check_dev_failure() if they want. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190903101605.2890-6-oohall@gmail.com
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-08 00:01:14 +0000