talos-op-linux/arch, branch v4.12.5

KVM: PPC: Book3S HV: Fix host crash on changing HPT size

2017-08-06T16:21:08+00:00

commit ef42719814db06fdfa26cd7566de0b64de173320 upstream. Commit f98a8bf9ee20 ("KVM: PPC: Book3S HV: Allow KVM_PPC_ALLOCATE_HTAB ioctl() to change HPT size", 2016-12-20) changed the behaviour of the KVM_PPC_ALLOCATE_HTAB ioctl so that it now allocates a new HPT and new revmap array if there was a previously-allocated HPT of a different size from the size being requested. In this case, we need to reset the rmap arrays of the memslots, because the rmap arrays will contain references to HPTEs which are no longer valid. Worse, these references are also references to slots in the new revmap array (which parallels the HPT), and the new revmap array contains random contents, since it doesn't get zeroed on allocation. The effect of having these stale references to slots in the revmap array that contain random contents is that subsequent calls to functions such as kvmppc_add_revmap_chain will crash because they will interpret the non-zero contents of the revmap array as HPTE indexes and thus index outside of the revmap array. This leads to host crashes such as the following. [ 7072.862122] Unable to handle kernel paging request for data at address 0xd000000c250c00f8 [ 7072.862218] Faulting instruction address: 0xc0000000000e1c78 [ 7072.862233] Oops: Kernel access of bad area, sig: 11 [#1] [ 7072.862286] SMP NR_CPUS=1024 [ 7072.862286] NUMA [ 7072.862325] PowerNV [ 7072.862378] Modules linked in: kvm_hv vhost_net vhost tap xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_conntrack ip_set nfnetlink ebtable_nat ebtable_broute bridge stp llc ip6table_mangle ip6table_security ip6table_raw iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw ebtable_filter ebtables ip6table_filter ip6_tables rpcrdma ib_isert iscsi_target_mod ib_iser libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm iw_cxgb3 mlx5_ib ib_core ses enclosure scsi_transport_sas ipmi_powernv ipmi_devintf ipmi_msghandler powernv_op_panel i2c_opal nfsd auth_rpcgss oid_registry [ 7072.863085] nfs_acl lockd grace sunrpc kvm_pr kvm xfs libcrc32c scsi_dh_alua dm_service_time radeon lpfc nvme_fc nvme_fabrics nvme_core scsi_transport_fc i2c_algo_bit tg3 drm_kms_helper ptp pps_core syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm dm_multipath i2c_core cxgb3 mlx5_core mdio [last unloaded: kvm_hv] [ 7072.863381] CPU: 72 PID: 56929 Comm: qemu-system-ppc Not tainted 4.12.0-kvm+ #59 [ 7072.863457] task: c000000fe29e7600 task.stack: c000001e3ffec000 [ 7072.863520] NIP: c0000000000e1c78 LR: c0000000000e2e3c CTR: c0000000000e25f0 [ 7072.863596] REGS: c000001e3ffef560 TRAP: 0300 Not tainted (4.12.0-kvm+) [ 7072.863658] MSR: 9000000100009033 [ 7072.863667] CR: 44082882 XER: 20000000 [ 7072.863767] CFAR: c0000000000e2e38 DAR: d000000c250c00f8 DSISR: 42000000 SOFTE: 1 GPR00: c0000000000e2e3c c000001e3ffef7e0 c000000001407d00 d000000c250c00f0 GPR04: d00000006509fb70 d00000000b3d2048 0000000003ffdfb7 0000000000000000 GPR08: 00000001007fdfb7 00000000c000000f d0000000250c0000 000000000070f7bf GPR12: 0000000000000008 c00000000fdad000 0000000010879478 00000000105a0d78 GPR16: 00007ffaf4080000 0000000000001190 0000000000000000 0000000000010000 GPR20: 4001ffffff000415 d00000006509fb70 0000000004091190 0000000ee1881190 GPR24: 0000000003ffdfb7 0000000003ffdfb7 00000000007fdfb7 c000000f5c958000 GPR28: d00000002d09fb70 0000000003ffdfb7 d00000006509fb70 d00000000b3d2048 [ 7072.864439] NIP [c0000000000e1c78] kvmppc_add_revmap_chain+0x88/0x130 [ 7072.864503] LR [c0000000000e2e3c] kvmppc_do_h_enter+0x84c/0x9e0 [ 7072.864566] Call Trace: [ 7072.864594] [c000001e3ffef7e0] [c000001e3ffef830] 0xc000001e3ffef830 (unreliable) [ 7072.864671] [c000001e3ffef830] [c0000000000e2e3c] kvmppc_do_h_enter+0x84c/0x9e0 [ 7072.864751] [c000001e3ffef920] [d00000000b38d878] kvmppc_map_vrma+0x168/0x200 [kvm_hv] [ 7072.864831] [c000001e3ffef9e0] [d00000000b38a684] kvmppc_vcpu_run_hv+0x1284/0x1300 [kvm_hv] [ 7072.864914] [c000001e3ffefb30] [d00000000f465664] kvmppc_vcpu_run+0x44/0x60 [kvm] [ 7072.865008] [c000001e3ffefb60] [d00000000f461864] kvm_arch_vcpu_ioctl_run+0x114/0x290 [kvm] [ 7072.865152] [c000001e3ffefbe0] [d00000000f453c98] kvm_vcpu_ioctl+0x598/0x7a0 [kvm] [ 7072.865292] [c000001e3ffefd40] [c000000000389328] do_vfs_ioctl+0xd8/0x8c0 [ 7072.865410] [c000001e3ffefde0] [c000000000389be4] SyS_ioctl+0xd4/0x130 [ 7072.865526] [c000001e3ffefe30] [c00000000000b760] system_call+0x58/0x6c [ 7072.865644] Instruction dump: [ 7072.865715] e95b2110 793a0020 7b4926e4 7f8a4a14 409e0098 807c000c 786326e4 7c6a1a14 [ 7072.865857] 935e0008 7bbd0020 813c000c 913e000c <93a30008> 93bc000c 48000038 60000000 [ 7072.866001] ---[ end trace 627b6e4bf8080edc ]--- Note that to trigger this, it is necessary to use a recent upstream QEMU (or other userspace that resizes the HPT at CAS time), specify a maximum memory size substantially larger than the current memory size, and boot a guest kernel that does not support HPT resizing. This fixes the problem by resetting the rmap arrays when the old HPT is freed. Fixes: f98a8bf9ee20 ("KVM: PPC: Book3S HV: Allow KVM_PPC_ALLOCATE_HTAB ioctl() to change HPT size") Reviewed-by: David Gibson Signed-off-by: Paul Mackerras Signed-off-by: Greg Kroah-Hartman

KVM: PPC: Book3S HV: Enable TM before accessing TM registers

2017-08-06T16:21:08+00:00

commit e47057151422a67ce08747176fa21cb3b526a2c9 upstream. Commit 46a704f8409f ("KVM: PPC: Book3S HV: Preserve userspace HTM state properly", 2017-06-15) added code to read transactional memory (TM) registers but forgot to enable TM before doing so. The result is that if userspace does have live values in the TM registers, a KVM_RUN ioctl will cause a host kernel crash like this: [ 181.328511] Unrecoverable TM Unavailable Exception f60 at d00000001e7d9980 [ 181.328605] Oops: Unrecoverable TM Unavailable Exception, sig: 6 [#1] [ 181.328613] SMP NR_CPUS=2048 [ 181.328613] NUMA [ 181.328618] PowerNV [ 181.328646] Modules linked in: vhost_net vhost tap nfs_layout_nfsv41_files rpcsec_gss_krb5 nfsv4 dns_resolver nfs +fscache xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat +nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 tun ebtable_filter ebtables +ip6table_filter ip6_tables iptable_filter bridge stp llc kvm_hv kvm nfsd ses enclosure scsi_transport_sas ghash_generic +auth_rpcgss gf128mul xts sg ctr nfs_acl lockd vmx_crypto shpchp ipmi_powernv i2c_opal grace ipmi_devintf i2c_core +powernv_rng sunrpc ipmi_msghandler ibmpowernv uio_pdrv_genirq uio leds_powernv powernv_op_panel ip_tables xfs sd_mod +lpfc ipr bnx2x libata mdio ptp pps_core scsi_transport_fc libcrc32c dm_mirror dm_region_hash dm_log dm_mod [ 181.329278] CPU: 40 PID: 9926 Comm: CPU 0/KVM Not tainted 4.12.0+ #1 [ 181.329337] task: c000003fc6980000 task.stack: c000003fe4d80000 [ 181.329396] NIP: d00000001e7d9980 LR: d00000001e77381c CTR: d00000001e7d98f0 [ 181.329465] REGS: c000003fe4d837e0 TRAP: 0f60 Not tainted (4.12.0+) [ 181.329523] MSR: 9000000000009033 [ 181.329527] CR: 24022448 XER: 00000000 [ 181.329608] CFAR: d00000001e773818 SOFTE: 1 [ 181.329608] GPR00: d00000001e77381c c000003fe4d83a60 d00000001e7ef410 c000003fdcfe0000 [ 181.329608] GPR04: c000003fe4f00000 0000000000000000 0000000000000000 c000003fd7954800 [ 181.329608] GPR08: 0000000000000001 c000003fc6980000 0000000000000000 d00000001e7e2880 [ 181.329608] GPR12: d00000001e7d98f0 c000000007b19000 00000001295220e0 00007fffc0ce2090 [ 181.329608] GPR16: 0000010011886608 00007fff8c89f260 0000000000000001 00007fff8c080028 [ 181.329608] GPR20: 0000000000000000 00000100118500a6 0000010011850000 0000010011850000 [ 181.329608] GPR24: 00007fffc0ce1b48 0000010011850000 00000000d673b901 0000000000000000 [ 181.329608] GPR28: 0000000000000000 c000003fdcfe0000 c000003fdcfe0000 c000003fe4f00000 [ 181.330199] NIP [d00000001e7d9980] kvmppc_vcpu_run_hv+0x90/0x6b0 [kvm_hv] [ 181.330264] LR [d00000001e77381c] kvmppc_vcpu_run+0x2c/0x40 [kvm] [ 181.330322] Call Trace: [ 181.330351] [c000003fe4d83a60] [d00000001e773478] kvmppc_set_one_reg+0x48/0x340 [kvm] (unreliable) [ 181.330437] [c000003fe4d83b30] [d00000001e77381c] kvmppc_vcpu_run+0x2c/0x40 [kvm] [ 181.330513] [c000003fe4d83b50] [d00000001e7700b4] kvm_arch_vcpu_ioctl_run+0x114/0x2a0 [kvm] [ 181.330586] [c000003fe4d83bd0] [d00000001e7642f8] kvm_vcpu_ioctl+0x598/0x7a0 [kvm] [ 181.330658] [c000003fe4d83d40] [c0000000003451b8] do_vfs_ioctl+0xc8/0x8b0 [ 181.330717] [c000003fe4d83de0] [c000000000345a64] SyS_ioctl+0xc4/0x120 [ 181.330776] [c000003fe4d83e30] [c00000000000b004] system_call+0x58/0x6c [ 181.330833] Instruction dump: [ 181.330869] e92d0260 e9290b50 e9290108 792807e3 41820058 e92d0260 e9290b50 e9290108 [ 181.330941] 792ae8a4 794a1f87 408204f4 e92d0260 <7d4022a6> f9490ff0 e92d0260 7d4122a6 [ 181.331013] ---[ end trace 6f6ddeb4bfe92a92 ]--- The fix is just to turn on the TM bit in the MSR before accessing the registers. Fixes: 46a704f8409f ("KVM: PPC: Book3S HV: Preserve userspace HTM state properly") Reported-by: Jan Stancek Tested-by: Jan Stancek Signed-off-by: Paul Mackerras Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Fix of_node_put() underflow during reconfig remove

2017-08-06T16:21:07+00:00

commit 4fd1bd443e80b12f0a01a45fb9a793206b41cb72 upstream. As for commit 68baf692c435 ("powerpc/pseries: Fix of_node_put() underflow during DLPAR remove"), the call to of_node_put() must be removed from pSeries_reconfig_remove_node(). dlpar_detach_node() and pSeries_reconfig_remove_node() both call of_detach_node(), and thus the node should not be released in both cases. Fixes: 0829f6d1f69e ("of: device_node kobject lifecycle fixes") Signed-off-by: Laurent Vivier Reviewed-by: David Gibson Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

parisc: Suspend lockup detectors before system halt

2017-08-06T16:21:07+00:00

commit 56188832a50f09998cb570ba3771a1d25c193c0e upstream. Some machines can't power off the machine, so disable the lockup detectors to avoid this watchdog BUG to show up every few seconds: watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [systemd-shutdow:1] Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman

parisc: Extend disabled preemption in copy_user_page

2017-08-06T16:21:06+00:00

commit 56008c04ebc099940021b714da2d7779117cf6a7 upstream. It's always bothered me that we only disable preemption in copy_user_page around the call to flush_dcache_page_asm. This patch extends this to after the copy. Signed-off-by: John David Anglin Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman

parisc: Prevent TLB speculation on flushed pages on CPUs that only support equivalent aliases

2017-08-06T16:21:06+00:00

commit ae7a609c34b6fb12328c553b5f9aab26ae74a28e upstream. Helge noticed that we flush the TLB page in flush_cache_page but not in flush_cache_range or flush_cache_mm. For a long time, we have had random segmentation faults building packages on machines with PA8800/8900 processors. These machines only support equivalent aliases. We don't see these faults on machines that don't require strict coherency. So, it appears TLB speculation sometimes leads to cache corruption on machines that require coherency. This patch adds TLB flushes to flush_cache_range and flush_cache_mm when coherency is required. We only flush the TLB in flush_cache_page when coherency is required. The patch also optimizes flush_cache_range. It turns out we always have the right context to use flush_user_dcache_range_asm and flush_user_icache_range_asm. The patch has been tested for some time on rp3440, rp3410 and A500-44. It's been boot tested on c8000. No random segmentation faults were observed during testing. Signed-off-by: John David Anglin Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman

MIPS: Fix a typo: s/preset/present/ in r2-to-r6 emulation error message

2017-07-27T22:10:19+00:00

commit 27fe2200dad2de8207a694024a7b9037dff1b280 upstream. This is a user-visible message, so we want it to be spelled correctly. Fixes: 5f9f41c474be ("MIPS: kernel: Prepare the JR instruction for emulation on MIPS R6") Signed-off-by: Maciej W. Rozycki Cc: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16400/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Send SIGILL for R6 branches in `__compute_return_epc_for_insn'

2017-07-27T22:10:19+00:00

commit a60b1a5bf88a250f1a77977c0224e502c901c77b upstream. Fix: * commit 8467ca0122e2 ("MIPS: Emulate the new MIPS R6 branch compact (BC) instruction"), * commit 84fef630127a ("MIPS: Emulate the new MIPS R6 BALC instruction"), * commit 69b9a2fd05a3 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC instructions"), * commit 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions"), * commit c893ce38b265 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions") and send SIGILL rather than returning -SIGILL for R6 branch and jump instructions. Returning -SIGILL is never correct as the API defines this function's result upon error to be -EFAULT and a signal actually issued. Fixes: 8467ca0122e2 ("MIPS: Emulate the new MIPS R6 branch compact (BC) instruction") Fixes: 84fef630127a ("MIPS: Emulate the new MIPS R6 BALC instruction") Fixes: 69b9a2fd05a3 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC instructions") Fixes: 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions") Fixes: c893ce38b265 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions") Signed-off-by: Maciej W. Rozycki Cc: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16399/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Send SIGILL for linked branches in `__compute_return_epc_for_insn'

2017-07-27T22:10:19+00:00

commit fef40be6da856afead4177aaa9d869a66fb3381f upstream. Fix commit 319824eabc3f ("MIPS: kernel: branch: Do not emulate the branch likelies on MIPS R6") and also send SIGILL rather than returning -SIGILL for BLTZAL, BLTZALL, BGEZAL and BGEZALL instruction encodings no longer supported in R6, except where emulated. Returning -SIGILL is never correct as the API defines this function's result upon error to be -EFAULT and a signal actually issued. Fixes: 319824eabc3f ("MIPS: kernel: branch: Do not emulate the branch likelies on MIPS R6") Signed-off-by: Maciej W. Rozycki Cc: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16398/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Rename `sigill_r6' to `sigill_r2r6' in `__compute_return_epc_for_insn'

2017-07-27T22:10:19+00:00

commit 1f4edde422961397cf4470b347958c13c6a740bb upstream. Use the more accurate `sigill_r2r6' name for the label used in the case of sending SIGILL in the absence of the instruction emulator for an earlier ISA level instruction that has been removed as from the R6 ISA, so that the `sigill_r6' name is freed for the situation where an R6 instruction is not supposed to be interpreted, because the executing processor does not support the R6 ISA. Signed-off-by: Maciej W. Rozycki Cc: James Hogan Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16397/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman