summaryrefslogtreecommitdiff
path: root/arch/powerpc
AgeCommit message (Collapse)AuthorFilesLines
2025-02-08powerpc/pseries/iommu: Don't unset window if it was never setShivaprasad G Bhat1-0/+3
commit 17391cb2613b82f8c405570fea605af3255ff8d2 upstream. On pSeries, when user attempts to use the same vfio container used by different iommu group, the spapr_tce_set_window() returns -EPERM and the subsequent cleanup leads to the below crash. Kernel attempted to read user page (308) - exploit attempt? BUG: Kernel NULL pointer dereference on read at 0x00000308 Faulting instruction address: 0xc0000000001ce358 Oops: Kernel access of bad area, sig: 11 [#1] NIP: c0000000001ce358 LR: c0000000001ce05c CTR: c00000000005add0 <snip> NIP [c0000000001ce358] spapr_tce_unset_window+0x3b8/0x510 LR [c0000000001ce05c] spapr_tce_unset_window+0xbc/0x510 Call Trace: spapr_tce_unset_window+0xbc/0x510 (unreliable) tce_iommu_attach_group+0x24c/0x340 [vfio_iommu_spapr_tce] vfio_container_attach_group+0xec/0x240 [vfio] vfio_group_fops_unl_ioctl+0x548/0xb00 [vfio] sys_ioctl+0x754/0x1580 system_call_exception+0x13c/0x330 system_call_vectored_common+0x15c/0x2ec <snip> --- interrupt: 3000 Fix this by having null check for the tbl passed to the spapr_tce_unset_window(). Fixes: f431a8cde7f1 ("powerpc/iommu: Reimplement the iommu_table_group_ops for pSeries") Cc: stable@vger.kernel.org Reported-by: Vaishnavi Bhat <vaish123@in.ibm.com> Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/173674009556.1559.12487885286848752833.stgit@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-08powerpc/pseries/iommu: IOMMU incorrectly marks MMIO range in DDWGaurav Batra2-4/+7
[ Upstream commit 8f70caad82e9c088ed93b4fea48d941ab6441886 ] Power Hypervisor can possibily allocate MMIO window intersecting with Dynamic DMA Window (DDW) range, which is over 32-bit addressing. These MMIO pages needs to be marked as reserved so that IOMMU doesn't map DMA buffers in this range. The current code is not marking these pages correctly which is resulting in LPAR to OOPS while booting. The stack is at below BUG: Unable to handle kernel data access on read at 0xc00800005cd40000 Faulting instruction address: 0xc00000000005cdac Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: af_packet rfkill ibmveth(X) lpfc(+) nvmet_fc nvmet nvme_keyring crct10dif_vpmsum nvme_fc nvme_fabrics nvme_core be2net(+) nvme_auth rtc_generic nfsd auth_rpcgss nfs_acl lockd grace sunrpc fuse configfs ip_tables x_tables xfs libcrc32c dm_service_time ibmvfc(X) scsi_transport_fc vmx_crypto gf128mul crc32c_vpmsum dm_mirror dm_region_hash dm_log dm_multipath dm_mod sd_mod scsi_dh_emc scsi_dh_rdac scsi_dh_alua t10_pi crc64_rocksoft_generic crc64_rocksoft sg crc64 scsi_mod Supported: Yes, External CPU: 8 PID: 241 Comm: kworker/8:1 Kdump: loaded Not tainted 6.4.0-150600.23.14-default #1 SLE15-SP6 b44ee71c81261b9e4bab5e0cde1f2ed891d5359b Hardware name: IBM,9080-M9S POWER9 (raw) 0x4e2103 0xf000005 of:IBM,FW950.B0 (VH950_149) hv:phyp pSeries Workqueue: events work_for_cpu_fn NIP: c00000000005cdac LR: c00000000005e830 CTR: 0000000000000000 REGS: c00001400c9ff770 TRAP: 0300 Not tainted (6.4.0-150600.23.14-default) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24228448 XER: 00000001 CFAR: c00000000005cdd4 DAR: c00800005cd40000 DSISR: 40000000 IRQMASK: 0 GPR00: c00000000005e830 c00001400c9ffa10 c000000001987d00 c00001400c4fe800 GPR04: 0000080000000000 0000000000000001 0000000004000000 0000000000800000 GPR08: 0000000004000000 0000000000000001 c00800005cd40000 ffffffffffffffff GPR12: 0000000084228882 c00000000a4c4f00 0000000000000010 0000080000000000 GPR16: c00001400c4fe800 0000000004000000 0800000000000000 c00000006088b800 GPR20: c00001401a7be980 c00001400eff3800 c000000002a2da68 000000000000002b GPR24: c0000000026793a8 c000000002679368 000000000000002a c0000000026793c8 GPR28: 000008007effffff 0000080000000000 0000000000800000 c00001400c4fe800 NIP [c00000000005cdac] iommu_table_reserve_pages+0xac/0x100 LR [c00000000005e830] iommu_init_table+0x80/0x1e0 Call Trace: [c00001400c9ffa10] [c00000000005e810] iommu_init_table+0x60/0x1e0 (unreliable) [c00001400c9ffa90] [c00000000010356c] iommu_bypass_supported_pSeriesLP+0x9cc/0xe40 [c00001400c9ffc30] [c00000000005c300] dma_iommu_dma_supported+0xf0/0x230 [c00001400c9ffcb0] [c00000000024b0c4] dma_supported+0x44/0x90 [c00001400c9ffcd0] [c00000000024b14c] dma_set_mask+0x3c/0x80 [c00001400c9ffd00] [c0080000555b715c] be_probe+0xc4/0xb90 [be2net] [c00001400c9ffdc0] [c000000000986f3c] local_pci_probe+0x6c/0x110 [c00001400c9ffe40] [c000000000188f28] work_for_cpu_fn+0x38/0x60 [c00001400c9ffe70] [c00000000018e454] process_one_work+0x314/0x620 [c00001400c9fff10] [c00000000018f280] worker_thread+0x2b0/0x620 [c00001400c9fff90] [c00000000019bb18] kthread+0x148/0x150 [c00001400c9fffe0] [c00000000000ded8] start_kernel_thread+0x14/0x18 There are 2 issues in the code 1. The index is "int" while the address is "unsigned long". This results in negative value when setting the bitmap. 2. The DMA offset is page shifted but the MMIO range is used as-is (64-bit address). MMIO address needs to be page shifted as well. Fixes: 3c33066a2190 ("powerpc/kernel/iommu: Add new iommu_table_in_use() helper") Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com> Reviewed-by: Nilay Shroff <nilay@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20241206210039.93172-1-gbatra@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-02-08powerpc/book3s64/hugetlb: Fix disabling hugetlb when fadump is activeSourabh Jain1-0/+9
[ Upstream commit d629d7a8efc33d05d62f4805c0ffb44727e3d99f ] Commit 8597538712eb ("powerpc/fadump: Do not use hugepages when fadump is active") disabled hugetlb support when fadump is active by returning early from hugetlbpage_init():arch/powerpc/mm/hugetlbpage.c and not populating hpage_shift/HPAGE_SHIFT. Later, commit 2354ad252b66 ("powerpc/mm: Update default hugetlb size early") moved the allocation of hpage_shift/HPAGE_SHIFT to early boot, which inadvertently re-enabled hugetlb support when fadump is active. Fix this by implementing hugepages_supported() on powerpc. This ensures that disabling hugetlb for the fadump kernel is independent of hpage_shift/HPAGE_SHIFT. Fixes: 2354ad252b66 ("powerpc/mm: Update default hugetlb size early") Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20241217074640.1064510-1-sourabhjain@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-02powerpc/pseries/vas: Add close() callback in vas_vm_ops structHaren Myneni1-0/+36
[ Upstream commit 05aa156e156ef3168e7ab8a68721945196495c17 ] The mapping VMA address is saved in VAS window struct when the paste address is mapped. This VMA address is used during migration to unmap the paste address if the window is active. The paste address mapping will be removed when the window is closed or with the munmap(). But the VMA address in the VAS window is not updated with munmap() which is causing invalid access during migration. The KASAN report shows: [16386.254991] BUG: KASAN: slab-use-after-free in reconfig_close_windows+0x1a0/0x4e8 [16386.255043] Read of size 8 at addr c00000014a819670 by task drmgr/696928 [16386.255096] CPU: 29 UID: 0 PID: 696928 Comm: drmgr Kdump: loaded Tainted: G B 6.11.0-rc5-nxgzip #2 [16386.255128] Tainted: [B]=BAD_PAGE [16386.255148] Hardware name: IBM,9080-HEX Power11 (architected) 0x820200 0xf000007 of:IBM,FW1110.00 (NH1110_016) hv:phyp pSeries [16386.255181] Call Trace: [16386.255202] [c00000016b297660] [c0000000018ad0ac] dump_stack_lvl+0x84/0xe8 (unreliable) [16386.255246] [c00000016b297690] [c0000000006e8a90] print_report+0x19c/0x764 [16386.255285] [c00000016b297760] [c0000000006e9490] kasan_report+0x128/0x1f8 [16386.255309] [c00000016b297880] [c0000000006eb5c8] __asan_load8+0xac/0xe0 [16386.255326] [c00000016b2978a0] [c00000000013f898] reconfig_close_windows+0x1a0/0x4e8 [16386.255343] [c00000016b297990] [c000000000140e58] vas_migration_handler+0x3a4/0x3fc [16386.255368] [c00000016b297a90] [c000000000128848] pseries_migrate_partition+0x4c/0x4c4 ... [16386.256136] Allocated by task 696554 on cpu 31 at 16377.277618s: [16386.256149] kasan_save_stack+0x34/0x68 [16386.256163] kasan_save_track+0x34/0x80 [16386.256175] kasan_save_alloc_info+0x58/0x74 [16386.256196] __kasan_slab_alloc+0xb8/0xdc [16386.256209] kmem_cache_alloc_noprof+0x200/0x3d0 [16386.256225] vm_area_alloc+0x44/0x150 [16386.256245] mmap_region+0x214/0x10c4 [16386.256265] do_mmap+0x5fc/0x750 [16386.256277] vm_mmap_pgoff+0x14c/0x24c [16386.256292] ksys_mmap_pgoff+0x20c/0x348 [16386.256303] sys_mmap+0xd0/0x160 ... [16386.256350] Freed by task 0 on cpu 31 at 16386.204848s: [16386.256363] kasan_save_stack+0x34/0x68 [16386.256374] kasan_save_track+0x34/0x80 [16386.256384] kasan_save_free_info+0x64/0x10c [16386.256396] __kasan_slab_free+0x120/0x204 [16386.256415] kmem_cache_free+0x128/0x450 [16386.256428] vm_area_free_rcu_cb+0xa8/0xd8 [16386.256441] rcu_do_batch+0x2c8/0xcf0 [16386.256458] rcu_core+0x378/0x3c4 [16386.256473] handle_softirqs+0x20c/0x60c [16386.256495] do_softirq_own_stack+0x6c/0x88 [16386.256509] do_softirq_own_stack+0x58/0x88 [16386.256521] __irq_exit_rcu+0x1a4/0x20c [16386.256533] irq_exit+0x20/0x38 [16386.256544] interrupt_async_exit_prepare.constprop.0+0x18/0x2c ... [16386.256717] Last potentially related work creation: [16386.256729] kasan_save_stack+0x34/0x68 [16386.256741] __kasan_record_aux_stack+0xcc/0x12c [16386.256753] __call_rcu_common.constprop.0+0x94/0xd04 [16386.256766] vm_area_free+0x28/0x3c [16386.256778] remove_vma+0xf4/0x114 [16386.256797] do_vmi_align_munmap.constprop.0+0x684/0x870 [16386.256811] __vm_munmap+0xe0/0x1f8 [16386.256821] sys_munmap+0x54/0x6c [16386.256830] system_call_exception+0x1a0/0x4a0 [16386.256841] system_call_vectored_common+0x15c/0x2ec [16386.256868] The buggy address belongs to the object at c00000014a819670 which belongs to the cache vm_area_struct of size 168 [16386.256887] The buggy address is located 0 bytes inside of freed 168-byte region [c00000014a819670, c00000014a819718) [16386.256915] The buggy address belongs to the physical page: [16386.256928] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14a81 [16386.256950] memcg:c0000000ba430001 [16386.256961] anon flags: 0x43ffff800000000(node=4|zone=0|lastcpupid=0x7ffff) [16386.256975] page_type: 0xfdffffff(slab) [16386.256990] raw: 043ffff800000000 c00000000501c080 0000000000000000 5deadbee00000001 [16386.257003] raw: 0000000000000000 00000000011a011a 00000001fdffffff c0000000ba430001 [16386.257018] page dumped because: kasan: bad access detected This patch adds close() callback in vas_vm_ops vm_operations_struct which will be executed during munmap() before freeing VMA. The VMA address in the VAS window is set to NULL after holding the window mmap_mutex. Fixes: 37e6764895ef ("powerpc/pseries/vas: Add VAS migration handler") Signed-off-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20241214051758.997759-1-haren@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-14powerpc/prom_init: Fixup missing powermac #size-cellsMichael Ellerman1-2/+27
[ Upstream commit cf89c9434af122f28a3552e6f9cc5158c33ce50a ] On some powermacs `escc` nodes are missing `#size-cells` properties, which is deprecated and now triggers a warning at boot since commit 045b14ca5c36 ("of: WARN on deprecated #address-cells/#size-cells handling"). For example: Missing '#size-cells' in /pci@f2000000/mac-io@c/escc@13000 WARNING: CPU: 0 PID: 0 at drivers/of/base.c:133 of_bus_n_size_cells+0x98/0x108 Hardware name: PowerMac3,1 7400 0xc0209 PowerMac ... Call Trace: of_bus_n_size_cells+0x98/0x108 (unreliable) of_bus_default_count_cells+0x40/0x60 __of_get_address+0xc8/0x21c __of_address_to_resource+0x5c/0x228 pmz_init_port+0x5c/0x2ec pmz_probe.isra.0+0x144/0x1e4 pmz_console_init+0x10/0x48 console_init+0xcc/0x138 start_kernel+0x5c4/0x694 As powermacs boot via prom_init it's possible to add the missing properties to the device tree during boot, avoiding the warning. Note that `escc-legacy` nodes are also missing `#size-cells` properties, but they are skipped by the macio driver, so leave them alone. Depends-on: 045b14ca5c36 ("of: WARN on deprecated #address-cells/#size-cells handling") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20241126025710.591683-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-09powerpc: Adjust adding stack protector flags to KBUILD_CLAGS for clangNathan Chancellor1-9/+4
commit bee08a9e6ab03caf14481d97b35a258400ffab8f upstream. After fixing the HAVE_STACKPROTECTER checks for clang's in-progress per-task stack protector support [1], the build fails during prepare0 because '-mstack-protector-guard-offset' has not been added to KBUILD_CFLAGS yet but the other '-mstack-protector-guard' flags have. clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default make[4]: *** [scripts/Makefile.build:229: scripts/mod/empty.o] Error 1 make[4]: *** [scripts/Makefile.build:102: scripts/mod/devicetable-offsets.s] Error 1 Mirror other architectures and add all '-mstack-protector-guard' flags to KBUILD_CFLAGS atomically during stack_protector_prepare, which resolves the issue and allows clang's implementation to fully work with the kernel. Cc: stable@vger.kernel.org # 6.1+ Link: https://github.com/llvm/llvm-project/pull/110928 [1] Reviewed-by: Keith Packard <keithp@keithp.com> Tested-by: Keith Packard <keithp@keithp.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241009-powerpc-fix-stackprotector-test-clang-v2-2-12fb86b31857@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09powerpc: Fix stack protector Kconfig test for clangNathan Chancellor1-2/+2
commit 46e1879deea22eed31e9425d58635895fc0e8040 upstream. Clang's in-progress per-task stack protector support [1] does not work with the current Kconfig checks because '-mstack-protector-guard-offset' is not provided, unlike all other architecture Kconfig checks. $ fd Kconfig -x rg -l mstack-protector-guard-offset ./arch/arm/Kconfig ./arch/riscv/Kconfig ./arch/arm64/Kconfig This produces an error from clang, which is interpreted as the flags not being supported at all when they really are. $ clang --target=powerpc64-linux-gnu \ -mstack-protector-guard=tls \ -mstack-protector-guard-reg=r13 \ -c -o /dev/null -x c /dev/null clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default This argument will always be provided by the build system, so mirror other architectures and use '-mstack-protector-guard-offset=0' for testing support, which fixes the issue for clang and does not regress support with GCC. Even with the first problem addressed, the 32-bit test continues to fail because Kbuild uses the powerpc64le-linux-gnu target for clang and nothing flips the target to 32-bit, resulting in an error about an invalid register valid: $ clang --target=powerpc64le-linux-gnu \ -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 \ -mstack-protector-guard-offset=0 \ -x c -c -o /dev/null /dev/null clang: error: invalid value 'r2' in 'mstack-protector-guard-reg=', expected one of: r13 While GCC allows arbitrary registers, the implementation of '-mstack-protector-guard=tls' in LLVM shares the same code path as the user space thread local storage implementation, which uses a fixed register (2 for 32-bit and 13 for 62-bit), so the command line parsing enforces this limitation. Use the Kconfig macro '$(m32-flag)', which expands to '-m32' when supported, in the stack protector support cc-option call to properly switch the target to a 32-bit one, which matches what happens in Kbuild. While the 64-bit macro does not strictly need it, add the equivalent 64-bit option for symmetry. Cc: stable@vger.kernel.org # 6.1+ Link: https://github.com/llvm/llvm-project/pull/110928 [1] Reviewed-by: Keith Packard <keithp@keithp.com> Tested-by: Keith Packard <keithp@keithp.com> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241009-powerpc-fix-stackprotector-test-clang-v2-1-12fb86b31857@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-09powerpc/vdso: Drop -mstack-protector-guard flags in 32-bit files with clangNathan Chancellor1-2/+6
commit d677ce521334d8f1f327cafc8b1b7854b0833158 upstream. Under certain conditions, the 64-bit '-mstack-protector-guard' flags may end up in the 32-bit vDSO flags, resulting in build failures due to the structure of clang's argument parsing of the stack protector options, which validates the arguments of the stack protector guard flags unconditionally in the frontend, choking on the 64-bit values when targeting 32-bit: clang: error: invalid value 'r13' in 'mstack-protector-guard-reg=', expected one of: r2 clang: error: invalid value 'r13' in 'mstack-protector-guard-reg=', expected one of: r2 make[3]: *** [arch/powerpc/kernel/vdso/Makefile:85: arch/powerpc/kernel/vdso/vgettimeofday-32.o] Error 1 make[3]: *** [arch/powerpc/kernel/vdso/Makefile:87: arch/powerpc/kernel/vdso/vgetrandom-32.o] Error 1 Remove these flags by adding them to the CC32FLAGSREMOVE variable, which already handles situations similar to this. Additionally, reformat and align a comment better for the expanding CONFIG_CC_IS_CLANG block. Cc: stable@vger.kernel.org # v6.1+ Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030-powerpc-vdso-drop-stackp-flags-clang-v1-1-d95e7376d29c@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05powerpc/pseries: Fix KVM guest detection for disabling hardlockup detectorGautam Menghani1-0/+1
commit 44e5d21e6d3fd2a1fed7f0327cf72e99397e2eaf upstream. As per the kernel documentation[1], hardlockup detector should be disabled in KVM guests as it may give false positives. On PPC, hardlockup detector is enabled inside KVM guests because disable_hardlockup_detector() is marked as early_initcall and it relies on kvm_guest static key (is_kvm_guest()) which is initialized later during boot by check_kvm_guest(), which is a core_initcall. check_kvm_guest() is also called in pSeries_smp_probe(), which is called before initcalls, but it is skipped if KVM guest does not have doorbell support or if the guest is launched with SMT=1. Call check_kvm_guest() in disable_hardlockup_detector() so that is_kvm_guest() check goes through fine and hardlockup detector can be disabled inside the KVM guest. [1]: Documentation/admin-guide/sysctl/kernel.rst Fixes: 633c8e9800f3 ("powerpc/pseries: Enable hardlockup watchdog for PowerVM partitions") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Gautam Menghani <gautam@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241108094839.33084-1-gautam@linux.ibm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-05powerpc/kexec: Fix return of uninitialized variableZhang Zekun1-2/+7
[ Upstream commit 83b5a407fbb73e6965adfb4bd0a803724bf87f96 ] of_property_read_u64() can fail and leave the variable uninitialized, which will then be used. Return error if reading the property failed. Fixes: 2e6bd221d96f ("powerpc/kexec_file: Enable early kernel OPAL calls") Signed-off-by: Zhang Zekun <zhangzekun11@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20240930075628.125138-1-zhangzekun11@huawei.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05KVM: PPC: Book3S HV: Fix kmv -> kvm typoKajol Jain3-5/+5
[ Upstream commit 590d2f9347f7974d7954400e5d937672fd844a8b ] Fix typo in the following kvm function names from: kmvhv_counters_tracepoint_regfunc -> kvmhv_counters_tracepoint_regfunc kmvhv_counters_tracepoint_unregfunc -> kvmhv_counters_tracepoint_unregfunc Fixes: e1f288d2f9c6 ("KVM: PPC: Book3S HV nestedv2: Add support for reading VPA counters for pseries guests") Reported-by: Madhavan Srinivasan <maddy@linux.ibm.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com> Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241114085020.1147912-1-kjain@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/sstep: make emulate_vsx_load and emulate_vsx_store staticMichal Suchanek2-13/+4
[ Upstream commit a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b ] These functions are not used outside of sstep.c Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05KVM: PPC: Book3S HV: Avoid returning to nested hypervisor on pending doorbellsGautam Menghani1-1/+0
[ Upstream commit 26686db69917399fa30e3b3135360771e90f83ec ] Commit 6398326b9ba1 ("KVM: PPC: Book3S HV P9: Stop using vc->dpdes") dropped the use of vcore->dpdes for msgsndp / SMT emulation. Prior to that commit, the below code at L1 level (see [1] for terminology) was responsible for setting vc->dpdes for the respective L2 vCPU: if (!nested) { kvmppc_core_prepare_to_enter(vcpu); if (vcpu->arch.doorbell_request) { vc->dpdes = 1; smp_wmb(); vcpu->arch.doorbell_request = 0; } L1 then sent vc->dpdes to L0 via kvmhv_save_hv_regs(), and while servicing H_ENTER_NESTED at L0, the below condition at L0 level made sure to abort and go back to L1 if vcpu->arch.doorbell_request = 1 so that L1 sets vc->dpdes as per above if condition: } else if (vcpu->arch.pending_exceptions || vcpu->arch.doorbell_request || xive_interrupt_pending(vcpu)) { vcpu->arch.ret = RESUME_HOST; goto out; } This worked fine since vcpu->arch.doorbell_request was used more like a flag and vc->dpdes was used to pass around the doorbell state. But after Commit 6398326b9ba1 ("KVM: PPC: Book3S HV P9: Stop using vc->dpdes"), vcpu->arch.doorbell_request is the only variable used to pass around doorbell state. With the plumbing for handling doorbells for nested guests updated to use vcpu->arch.doorbell_request over vc->dpdes, the above "else if" stops doorbells from working correctly as L0 aborts execution of L2 and instead goes back to L1. Remove vcpu->arch.doorbell_request from the above "else if" condition as it is no longer needed for L0 to correctly handle the doorbell status while running L2. [1] Terminology 1. L0 : PowerNV linux running with HV privileges 2. L1 : Pseries KVM guest running on top of L0 2. L2 : Nested KVM guest running on top of L1 Fixes: 6398326b9ba1 ("KVM: PPC: Book3S HV P9: Stop using vc->dpdes") Signed-off-by: Gautam Menghani <gautam@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241109063301.105289-4-gautam@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05KVM: PPC: Book3S HV: Stop using vc->dpdes for nested KVM guestsGautam Menghani2-4/+19
[ Upstream commit 0d3c6b28896f9889c8864dab469e0343a0ad1c0c ] commit 6398326b9ba1 ("KVM: PPC: Book3S HV P9: Stop using vc->dpdes") introduced an optimization to use only vcpu->doorbell_request for SMT emulation for Power9 and above guests, but the code for nested guests still relies on the old way of handling doorbells, due to which an L2 guest (see [1]) cannot be booted with XICS with SMT>1. The command to repro this issue is: // To be run in L1 qemu-system-ppc64 \ -drive file=rhel.qcow2,format=qcow2 \ -m 20G \ -smp 8,cores=1,threads=8 \ -cpu host \ -nographic \ -machine pseries,ic-mode=xics -accel kvm Fix the plumbing to utilize vcpu->doorbell_request instead of vcore->dpdes for nested KVM guests on P9 and above. [1] Terminology 1. L0 : PowerNV linux running with HV privileges 2. L1 : Pseries KVM guest running on top of L0 2. L2 : Nested KVM guest running on top of L1 Fixes: 6398326b9ba1 ("KVM: PPC: Book3S HV P9: Stop using vc->dpdes") Signed-off-by: Gautam Menghani <gautam@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241109063301.105289-3-gautam@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05fadump: reserve param area if below boot_mem_topSourabh Jain1-1/+1
[ Upstream commit fb90dca828b6070709093934c6dec56489a2d91d ] The param area is a memory region where the kernel places additional command-line arguments for fadump kernel. Currently, the param memory area is reserved in fadump kernel if it is above boot_mem_top. However, it should be reserved if it is below boot_mem_top because the fadump kernel already reserves memory from boot_mem_top to the end of DRAM. Currently, there is no impact from not reserving param memory if it is below boot_mem_top, as it is not used after the early boot phase of the fadump kernel. However, if this changes in the future, it could lead to issues in the fadump kernel. Fixes: 3416c9daa6b1 ("powerpc/fadump: pass additional parameters when fadump is active") Acked-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241107055817.489795-2-sourabhjain@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/fadump: allocate memory for additional parameters earlyHari Bathini3-5/+15
[ Upstream commit f4892c68ecc1cf45e41a78820dd2eebccc945b66 ] Memory for passing additional parameters to fadump capture kernel is allocated during subsys_initcall level, using memblock. But as slab is already available by this time, allocation happens via the buddy allocator. This may work for radix MMU but is likely to fail in most cases for hash MMU as hash MMU needs this memory in the first memory block for it to be accessible in real mode in the capture kernel (second boot). So, allocate memory for additional parameters area as soon as MMU mode is obvious. Fixes: 683eab94da75 ("powerpc/fadump: setup additional parameters for dump capture kernel") Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com> Closes: https://lore.kernel.org/lkml/a70e4064-a040-447b-8556-1fd02f19383d@linux.vnet.ibm.com/T/#u Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Tested-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241107055817.489795-1-sourabhjain@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/pseries: Fix dtl_access_lock to be a rw_semaphoreMichael Ellerman3-10/+10
[ Upstream commit cadae3a45d23aa4f6485938a67cbc47aaaa25e38 ] The dtl_access_lock needs to be a rw_sempahore, a sleeping lock, because the code calls kmalloc() while holding it, which can sleep: # echo 1 > /proc/powerpc/vcpudispatch_stats BUG: sleeping function called from invalid context at include/linux/sched/mm.h:337 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 199, name: sh preempt_count: 1, expected: 0 3 locks held by sh/199: #0: c00000000a0743f8 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x324/0x438 #1: c0000000028c7058 (dtl_enable_mutex){+.+.}-{3:3}, at: vcpudispatch_stats_write+0xd4/0x5f4 #2: c0000000028c70b8 (dtl_access_lock){+.+.}-{2:2}, at: vcpudispatch_stats_write+0x220/0x5f4 CPU: 0 PID: 199 Comm: sh Not tainted 6.10.0-rc4 #152 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries Call Trace: dump_stack_lvl+0x130/0x148 (unreliable) __might_resched+0x174/0x410 kmem_cache_alloc_noprof+0x340/0x3d0 alloc_dtl_buffers+0x124/0x1ac vcpudispatch_stats_write+0x2a8/0x5f4 proc_reg_write+0xf4/0x150 vfs_write+0xfc/0x438 ksys_write+0x88/0x148 system_call_exception+0x1c4/0x5a0 system_call_common+0xf4/0x258 Fixes: 06220d78f24a ("powerpc/pseries: Introduce rwlock to gatekeep DTLB usage") Tested-by: Kajol Jain <kjain@linux.ibm.com> Reviewed-by: Nysal Jan K.A <nysal@linux.ibm.com> Reviewed-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20240819122401.513203-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/mm/fault: Fix kfence page fault reportingRitesh Harjani (IBM)1-2/+8
[ Upstream commit 06dbbb4d5f7126b6307ab807cbf04ecfc459b933 ] copy_from_kernel_nofault() can be called when doing read of /proc/kcore. /proc/kcore can have some unmapped kfence objects which when read via copy_from_kernel_nofault() can cause page faults. Since *_nofault() functions define their own fixup table for handling fault, use that instead of asking kfence to handle such faults. Hence we search the exception tables for the nip which generated the fault. If there is an entry then we let the fixup table handler handle the page fault by returning an error from within ___do_page_fault(). This can be easily triggered if someone tries to do dd from /proc/kcore. eg. dd if=/proc/kcore of=/dev/null bs=1M Some example false negatives: =============================== BUG: KFENCE: invalid read in copy_from_kernel_nofault+0x9c/0x1a0 Invalid read at 0xc0000000fdff0000: copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec BUG: KFENCE: use-after-free read in copy_from_kernel_nofault+0x9c/0x1a0 Use-after-free read at 0xc0000000fe050000 (in kfence-#2): copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec Fixes: 90cbac0e995d ("powerpc: Enable KFENCE for PPC32") Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reported-by: Disha Goel <disgoel@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/a411788081d50e3b136c6270471e35aba3dfafa3.1729271995.git.ritesh.list@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init()Ritesh Harjani (IBM)3-7/+12
[ Upstream commit 05b94cae1c47f94588c3e7096963c1007c4d9c1d ] During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE, since pageblock_order is still zero and it gets initialized later during initmem_init() e.g. setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order() One such use case where this causes issue is - early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init() This causes CMA memory alignment check to be bypassed in cma_init_reserved_mem(). Then later cma_activate_area() can hit a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory area was not pageblock_order aligned. Fix it by moving the fadump_cma_init() after initmem_init(), where other such cma reservations also gets called. <stack trace> ============== page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010 flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:778! Call Trace: __free_one_page+0x57c/0x7b0 (unreliable) free_pcppages_bulk+0x1a8/0x2c8 free_unref_page_commit+0x3d4/0x4e4 free_unref_page+0x458/0x6d0 init_cma_reserved_pageblock+0x114/0x198 cma_init_reserved_areas+0x270/0x3e0 do_one_initcall+0x80/0x2f8 kernel_init_freeable+0x33c/0x530 kernel_init+0x34/0x26c ret_from_kernel_user_thread+0x14/0x1c Fixes: 11ac3e87ce09 ("mm: cma: use pageblock_order as the single alignment") Suggested-by: David Hildenbrand <david@redhat.com> Reported-by: Sachin P Bappalige <sachinpb@linux.ibm.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/fadump: Refactor and prepare fadump_cma_init for late initRitesh Harjani (IBM)1-14/+9
[ Upstream commit adfaec30ffaceecd565e06adae367aa944acc3c9 ] We anyway don't use any return values from fadump_cma_init(). Since fadump_reserve_mem() from where fadump_cma_init() gets called today, already has the required checks. This patch makes this function return type as void. Let's also handle extra cases like return if fadump_supported is false or dump_active, so that in later patches we can call fadump_cma_init() separately from setup_arch(). Acked-by: Hari Bathini <hbathini@linux.ibm.com> Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/a2afc3d6481a87a305e89cfc4a3f3d2a0b8ceab3.1729146153.git.ritesh.list@gmail.com Stable-dep-of: 05b94cae1c47 ("powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init()") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05powerpc/vdso: Flag VDSO64 entry points as functionsChristophe Leroy1-0/+1
[ Upstream commit 0161bd38c24312853ed5ae9a425a1c41c4ac674a ] On powerpc64 as shown below by readelf, vDSO functions symbols have type NOTYPE. $ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg ELF Header: Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00 Class: ELF64 Data: 2's complement, big endian Version: 1 (current) OS/ABI: UNIX - System V ABI Version: 0 Type: DYN (Shared object file) Machine: PowerPC64 Version: 0x1 ... Symbol table '.dynsym' contains 12 entries: Num: Value Size Type Bind Vis Ndx Name ... 1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 ... 4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15 Symbol table '.symtab' contains 56 entries: Num: Value Size Type Bind Vis Ndx Name ... 45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15 46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu 47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64") was applied to have selftests also look for NOTYPE symbols, but the correct fix should be to flag VDSO entry points as functions. The original commit that brought VDSO support into powerpc/64 has the following explanation: Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps can't be expected to link against them directly, the vDSO's are both seen as if they were linked at 0 and the symbols just contain offsets to the various functions. This is done on purpose to avoid a relocation step (ppc64 functions normally have descriptors with abs addresses in them). When glibc uses those functions, it's expected to use it's own trampolines that know how to reach them. The descriptors it's talking about are the OPD function descriptors used on ABI v1 (big endian). But it would be more correct for a text symbol to have type function, even if there's no function descriptor for it. glibc has a special case already for handling the VDSO symbols which creates a fake opd pointing at the kernel symbol. So changing the VDSO symbol type to function shouldn't affect that. For ABI v2, there is no function descriptors and VDSO functions can safely have function type. So lets flag VDSO entry points as functions and revert the selftest change. Link: https://github.com/mpe/linux-fullhistory/commit/5f2dd691b62da9d9cc54b938f8b29c22c93cb805 Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-By: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-12-05of/fdt: add dt_phys arg to early_init_dt_scan and early_init_dt_verifyUsama Arif3-3/+3
[ Upstream commit b2473a359763e27567993e7d8f37de82f57a0829 ] __pa() is only intended to be used for linear map addresses and using it for initial_boot_params which is in fixmap for arm64 will give an incorrect value. Hence save the physical address when it is known at boot time when calling early_init_dt_scan for arm64 and use it at kexec time instead of converting the virtual address using __pa(). Note that arm64 doesn't need the FDT region reserved in the DT as the kernel explicitly reserves the passed in FDT. Therefore, only a debug warning is fixed with this change. Reported-by: Breno Leitao <leitao@debian.org> Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Usama Arif <usamaarif642@gmail.com> Fixes: ac10be5cdbfa ("arm64: Use common of_kexec_alloc_and_setup_fdt()") Link: https://lore.kernel.org/r/20241023171426.452688-1-usamaarif642@gmail.com Signed-off-by: Rob Herring (Arm) <robh@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-16Merge tag 'mm-hotfixes-stable-2024-11-16-15-33' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull hotfixes from Andrew Morton: "10 hotfixes, 7 of which are cc:stable. All singletons, please see the changelogs for details" * tag 'mm-hotfixes-stable-2024-11-16-15-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm: revert "mm: shmem: fix data-race in shmem_getattr()" ocfs2: uncache inode which has failed entering the group mm: fix NULL pointer dereference in alloc_pages_bulk_noprof mm, doc: update read_ahead_kb for MADV_HUGEPAGE fs/proc/task_mmu: prevent integer overflow in pagemap_scan_get_args() sched/task_stack: fix object_is_on_stack() for KASAN tagged pointers crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32 mm/mremap: fix address wraparound in move_page_tables() tools/mm: fix compile error mm, swap: fix allocation and scanning race with swapoff
2024-11-14crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32Dave Vasilevsky1-0/+4
Fixes boot failures on 6.9 on PPC_BOOK3S_32 machines using Open Firmware. On these machines, the kernel refuses to boot from non-zero PHYSICAL_START, which occurs when CRASH_DUMP is on. Since most PPC_BOOK3S_32 machines boot via Open Firmware, it should default to off for them. Users booting via some other mechanism can still turn it on explicitly. Does not change the default on any other architectures for the time being. Link: https://lkml.kernel.org/r/20240917163720.1644584-1-dave@vasilevsky.ca Fixes: 75bc255a7444 ("crash: clean up kdump related config items") Signed-off-by: Dave Vasilevsky <dave@vasilevsky.ca> Reported-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de> Closes: https://lists.debian.org/debian-powerpc/2024/07/msg00001.html Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Acked-by: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Reimar Döffinger <Reimar.Doeffinger@gmx.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-06KVM: PPC: Book3S HV: Mask off LPCR_MER for a vCPU before running it to avoid ↵Gautam Menghani1-0/+12
spurious interrupts Running a L2 vCPU (see [1] for terminology) with LPCR_MER bit set and no pending interrupts results in that L2 vCPU getting an infinite flood of spurious interrupts. The 'if check' in kvmhv_run_single_vcpu() sets the LPCR_MER bit if there are pending interrupts. The spurious flood problem can be observed in 2 cases: 1. Crashing the guest while interrupt heavy workload is running a. Start a L2 guest and run an interrupt heavy workload (eg: ipistorm) b. While the workload is running, crash the guest (make sure kdump is configured) c. Any one of the vCPUs of the guest will start getting an infinite flood of spurious interrupts. 2. Running LTP stress tests in multiple guests at the same time a. Start 4 L2 guests. b. Start running LTP stress tests on all 4 guests at same time. c. In some time, any one/more of the vCPUs of any of the guests will start getting an infinite flood of spurious interrupts. The root cause of both the above issues is the same: 1. A NMI is sent to a running vCPU that has LPCR_MER bit set. 2. In the NMI path, all registers are refreshed, i.e, H_GUEST_GET_STATE is called for all the registers. 3. When H_GUEST_GET_STATE is called for LPCR, the vcpu->arch.vcore->lpcr of that vCPU at L1 level gets updated with LPCR_MER set to 1, and this new value is always used whenever that vCPU runs, regardless of whether there was a pending interrupt. 4. Since LPCR_MER is set, the vCPU in L2 always jumps to the external interrupt handler, and this cycle never ends. Fix the spurious flood by masking off the LPCR_MER bit before running a L2 vCPU to ensure that it is not set if there are no pending interrupts. [1] Terminology: 1. L0 : PAPR hypervisor running in HV mode 2. L1 : Linux guest (logical partition) running on top of L0 3. L2 : KVM guest running on top of L1 Fixes: ec0f6639fa88 ("KVM: PPC: Book3S HV nestedv2: Ensure LPCR_MER bit is passed to the L0") Cc: stable@vger.kernel.org # v6.8+ Signed-off-by: Gautam Menghani <gautam@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
2024-10-16powerpc/powernv: Free name on error in opal_event_init()Michael Ellerman1-0/+1
In opal_event_init() if request_irq() fails name is not freed, leading to a memory leak. The code only runs at boot time, there's no way for a user to trigger it, so there's no security impact. Fix the leak by freeing name in the error path. Reported-by: 2639161967 <2639161967@qq.com> Closes: https://lore.kernel.org/linuxppc-dev/87wmjp3wig.fsf@mail.lhotse Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20240920093520.67997-1-mpe@ellerman.id.au
2024-10-11powerpc/8xx: Fix kernel DTLB miss on dcbzChristophe Leroy1-0/+1
Following OOPS is encountered while loading test_bpf module on powerpc 8xx: [ 218.835567] BUG: Unable to handle kernel data access on write at 0xcb000000 [ 218.842473] Faulting instruction address: 0xc0017a80 [ 218.847451] Oops: Kernel access of bad area, sig: 11 [#1] [ 218.852854] BE PAGE_SIZE=16K PREEMPT CMPC885 [ 218.857207] SAF3000 DIE NOTIFICATION [ 218.860713] Modules linked in: test_bpf(+) test_module [ 218.865867] CPU: 0 UID: 0 PID: 527 Comm: insmod Not tainted 6.11.0-s3k-dev-09856-g3de3d71ae2e6-dirty #1280 [ 218.875546] Hardware name: MIAE 8xx 0x500000 CMPC885 [ 218.880521] NIP: c0017a80 LR: beab859c CTR: 000101d4 [ 218.885584] REGS: cac2bc90 TRAP: 0300 Not tainted (6.11.0-s3k-dev-09856-g3de3d71ae2e6-dirty) [ 218.894308] MSR: 00009032 <EE,ME,IR,DR,RI> CR: 55005555 XER: a0007100 [ 218.901290] DAR: cb000000 DSISR: c2000000 [ 218.901290] GPR00: 000185d1 cac2bd50 c21b9580 caf7c030 c3883fcc 00000008 cafffffc 00000000 [ 218.901290] GPR08: 00040000 18300000 20000000 00000004 99005555 100d815e ca669d08 00000369 [ 218.901290] GPR16: ca730000 00000000 ca2c004c 00000000 00000000 0000035d 00000311 00000369 [ 218.901290] GPR24: ca732240 00000001 00030ba3 c3800000 00000000 00185d48 caf7c000 ca2c004c [ 218.941087] NIP [c0017a80] memcpy+0x88/0xec [ 218.945277] LR [beab859c] test_bpf_init+0x22c/0x3c90 [test_bpf] [ 218.951476] Call Trace: [ 218.953916] [cac2bd50] [beab8570] test_bpf_init+0x200/0x3c90 [test_bpf] (unreliable) [ 218.962034] [cac2bde0] [c0004c04] do_one_initcall+0x4c/0x1fc [ 218.967706] [cac2be40] [c00a2ec4] do_init_module+0x68/0x360 [ 218.973292] [cac2be60] [c00a5194] init_module_from_file+0x8c/0xc0 [ 218.979401] [cac2bed0] [c00a5568] sys_finit_module+0x250/0x3f0 [ 218.985248] [cac2bf20] [c000e390] system_call_exception+0x8c/0x15c [ 218.991444] [cac2bf30] [c00120a8] ret_from_syscall+0x0/0x28 This happens in the main loop of memcpy() ==> c0017a80: 7c 0b 37 ec dcbz r11,r6 c0017a84: 80 e4 00 04 lwz r7,4(r4) c0017a88: 81 04 00 08 lwz r8,8(r4) c0017a8c: 81 24 00 0c lwz r9,12(r4) c0017a90: 85 44 00 10 lwzu r10,16(r4) c0017a94: 90 e6 00 04 stw r7,4(r6) c0017a98: 91 06 00 08 stw r8,8(r6) c0017a9c: 91 26 00 0c stw r9,12(r6) c0017aa0: 95 46 00 10 stwu r10,16(r6) c0017aa4: 42 00 ff dc bdnz c0017a80 <memcpy+0x88> Commit ac9f97ff8b32 ("powerpc/8xx: Inconditionally use task PGDIR in DTLB misses") relies on re-reading DAR register to know if an error is due to a missing copy of a PMD entry in task's PGDIR, allthough DAR was already read in the exception prolog and copied into thread struct. This is because is it done very early in the exception and there are not enough registers available to keep a pointer to thread struct. However, dcbz instruction is buggy and doesn't update DAR register on fault. That is detected and generates a call to FixupDAR workaround which updates DAR copy in thread struct but doesn't fix DAR register. Let's fix DAR in addition to the update of DAR copy in thread struct. Fixes: ac9f97ff8b32 ("powerpc/8xx: Inconditionally use task PGDIR in DTLB misses") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/2b851399bd87e81c6ccb87ea3a7a6b32c7aa04d7.1728118396.git.christophe.leroy@csgroup.eu
2024-10-06Merge tag 'powerpc-6.12-3' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fix from Michael Ellerman: - Allow r30 to be used in vDSO code generation of getrandom Thanks to Jason A. Donenfeld * tag 'powerpc-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/vdso: allow r30 in vDSO code generation of getrandom
2024-10-02move asm/unaligned.h to linux/unaligned.hAl Viro3-3/+3
asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-09-30powerpc/vdso: allow r30 in vDSO code generation of getrandomJason A. Donenfeld1-1/+1
For gettimeofday, -f