From: Michael Ellerman <mpe@ellerman.id.au>
To: Nicholas Piggin <npiggin@gmail.com>, kvm-ppc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [PATCH v1 26/55] KVM: PPC: Book3S HV: Change dec_expires to be relative to guest timebase
Date: Sat, 07 Aug 2021 23:17:34 +0000 [thread overview]
Message-ID: <87y29cn8tt.fsf@mpe.ellerman.id.au> (raw)
In-Reply-To: <20210726035036.739609-27-npiggin@gmail.com>
Nicholas Piggin <npiggin@gmail.com> writes:
> Change dec_expires to be relative to the guest timebase, and allow
> it to be moved into low level P9 guest entry functions, to improve
> SPR access scheduling.
>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> arch/powerpc/include/asm/kvm_book3s.h | 6 +++
> arch/powerpc/include/asm/kvm_host.h | 2 +-
> arch/powerpc/kvm/book3s_hv.c | 58 +++++++++++++------------
> arch/powerpc/kvm/book3s_hv_nested.c | 3 ++
> arch/powerpc/kvm/book3s_hv_p9_entry.c | 10 ++++-
> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 14 ------
> 6 files changed, 49 insertions(+), 44 deletions(-)
My p8 is hitting an oops running guests, and bisect points to this. Not
obvious how the change relates to the oops, but maybe you can see it.
cheers
[ 716.042962][T16989] Kernel attempted to read user page (0) - exploit attempt? (uid: 0)
[ 716.043020][T16989] BUG: Kernel NULL pointer dereference on read at 0x00000000
[ 716.043028][T16989] Faulting instruction address: 0xc00000000001e1a8
[ 716.043037][T16989] Oops: Kernel access of bad area, sig: 11 [#1]
[ 716.043043][T16989] LE PAGE_SIZEdK MMU=Hash SMP NR_CPUS 48 NUMA PowerNV
[ 716.043052][T16989] Modules linked in: xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nfnetlink ip6table_filter ip6_tables iptable_filter tun bridge stp llc fuse kvm_hv kvm binfmt_misc squashfs mlx4_ib ib_uverbs dm_multipath scsi_dh_rdac ib_core scsi_dh_alua mlx4_en sr_mod cdrom lpfc sg mlx4_core bnx2x crc_t10dif crct10dif_generic scsi_transport_fc mdio vmx_crypto gf128mul crct10dif_vpmsum crct10dif_common leds_powernv powernv_rng led_class crc32c_vpmsum rng_core powernv_op_panel sunrpc ip_tables x_tables autofs4
[ 716.043128][T16989] CPU: 56 PID: 16989 Comm: qemu-system-ppc Not tainted 5.14.0-rc4-02329-g9bdd37071243 #1
[ 716.043137][T16989] NIP: c00000000001e1a8 LR: c00000000001e154 CTR: c00000000016ebb0
[ 716.043144][T16989] REGS: c0000009f1a93480 TRAP: 0300 Not tainted (5.14.0-rc4-02329-g9bdd37071243)
[ 716.043150][T16989] MSR: 9000000002803033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE> CR: 42442444 XER: 20000000
[ 716.043167][T16989] CFAR: c00000000000cd0c DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 3
[ 716.043167][T16989] GPR00: c00000000001eab8 c0000009f1a93720 c000000002459f00 c0000009c0730270
[ 716.043167][T16989] GPR04: 00000000000001f0 0000000000000000 0000000022442448 c0000009c072ec80
[ 716.043167][T16989] GPR08: 00000000000000c2 0000000044000000 9000000002803033 0000000000000001
[ 716.043167][T16989] GPR12: 0000000000002200 c000000ffffec600 00007fff955f4410 0000000000000000
[ 716.043167][T16989] GPR16: 00007fff96280000 00007fff955f0320 00007fff8ee8ebe0 00007fff8e660028
[ 716.043167][T16989] GPR20: c000000803807400 c000000858b243bc 000000000000000a c000000002496eb8
[ 716.043167][T16989] GPR24: c000000801123650 c0000009c0730250 c0000009c072ec80 0000000002802000
[ 716.043167][T16989] GPR28: 0000000000800000 0000000002802000 0000000000800000 c0000009f1a93e80
[ 716.043236][T16989] NIP [c00000000001e1a8] restore_math+0x208/0x310
[ 716.043247][T16989] LR [c00000000001e154] restore_math+0x1b4/0x310
[ 716.043254][T16989] Call Trace:
[ 716.043257][T16989] [c0000009f1a93720] [0000000022442448] 0x22442448 (unreliable)
[ 716.043267][T16989] [c0000009f1a93780] [c00000000001eab8] __switch_to+0x228/0x2f0
[ 716.043274][T16989] [c0000009f1a937e0] [c000000000f7949c] __schedule+0x40c/0xf10
[ 716.043283][T16989] [c0000009f1a938b0] [c000000000f7a034] schedule+0x94/0x170
[ 716.043291][T16989] [c0000009f1a938e0] [c00800000b8e4474] kvmppc_wait_for_exec+0xdc/0xf8 [kvm_hv]
[ 716.043307][T16989] [c0000009f1a93960] [c00800000b8eeb18] kvmppc_vcpu_run_hv+0x900/0x10f0 [kvm_hv]
[ 716.043319][T16989] [c0000009f1a93a10] [c00800000b76355c] kvmppc_vcpu_run+0x34/0x48 [kvm]
[ 716.043340][T16989] [c0000009f1a93a30] [c00800000b75f188] kvm_arch_vcpu_ioctl_run+0x340/0x450 [kvm]
[ 716.043359][T16989] [c0000009f1a93ac0] [c00800000b74d470] kvm_vcpu_ioctl+0x328/0x8f8 [kvm]
[ 716.043378][T16989] [c0000009f1a93ca0] [c0000000004fe9d4] sys_ioctl+0x6b4/0x13b0
[ 716.043386][T16989] [c0000009f1a93db0] [c00000000002f918] system_call_exception+0x168/0x290
[ 716.043394][T16989] [c0000009f1a93e10] [c00000000000c864] system_call_common+0xf4/0x258
[ 716.043402][T16989] --- interrupt: c00 at 0x7fff954af010
[ 716.043407][T16989] NIP: 00007fff954af010 LR: 0000000116243430 CTR: 0000000000000000
[ 716.043413][T16989] REGS: c0000009f1a93e80 TRAP: 0c00 Not tainted (5.14.0-rc4-02329-g9bdd37071243)
[ 716.043419][T16989] MSR: 900000000000d033 <SF,HV,EE,PR,ME,IR,DR,RI,LE> CR: 22444442 XER: 00000000
[ 716.043434][T16989] IRQMASK: 0
[ 716.043434][T16989] GPR00: 0000000000000036 00007fff8ee8dc30 00007fff955a7100 000000000000000f
[ 716.043434][T16989] GPR04: 000000002000ae80 0000000000000000 00000000000004fb 0000000000000000
[ 716.043434][T16989] GPR08: 000000000000000f 0000000000000000 0000000000000000 0000000000000000
[ 716.043434][T16989] GPR12: 0000000000000000 00007fff8ee96290 00007fff955f4410 0000000000000000
[ 716.043434][T16989] GPR16: 00007fff96280000 00007fff955f0320 00007fff8ee8ebe0 00007fff8e660028
[ 716.043434][T16989] GPR20: 0000000000000000 0000000000000000 000000011689b0d0 000000002000ae80
[ 716.043434][T16989] GPR24: 00007fff8ffa00ae 0000000000000000 00007fff8ee8f290 00007fff8ffb0010
[ 716.043434][T16989] GPR28: 0000000116e010e0 00007fff8ffb0010 0000000000000000 000000002000ae80
[ 716.043498][T16989] NIP [00007fff954af010] 0x7fff954af010
[ 716.043503][T16989] LR [0000000116243430] 0x116243430
[ 716.043507][T16989] --- interrupt: c00
[ 716.043511][T16989] Instruction dump:
[ 716.043517][T16989] fb610038 67db0200 9907185a 4182005c 7c0802a6 7f63db78 f8010070 4bffeeed
[ 716.043529][T16989] 2c3e0000 408200d4 547ddb78 0082812b <eb000000> 387a1860 7fdcf378 7f7edb78
[ 716.043543][T16989] ---[ end trace b02ece1d913ff866 ]---
next prev parent reply other threads:[~2021-08-07 23:17 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-26 3:49 [PATCH v1 00/55] KVM: PPC: Book3S HV P9: entry/exit optimisations Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 01/55] KVM: PPC: Book3S HV: Remove TM emulation from POWER7/8 path Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 02/55] KVM: PPC: Book3S HV P9: Fixes for TM softpatch interrupt Nicholas Piggin
2021-08-06 1:16 ` Michael Ellerman
2021-08-06 10:25 ` Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 03/55] KVM: PPC: Book3S HV: Sanitise vcpu registers in nested path Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 04/55] KVM: PPC: Book3S HV: Stop forwarding all HFUs to L1 Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 05/55] KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs are live Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 06/55] powerpc/64s: Remove WORT SPR from POWER9/10 Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 07/55] KMV: PPC: Book3S HV P9: Use set_dec to set decrementer to host Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 08/55] KVM: PPC: Book3S HV P9: Use host timer accounting to avoid decrementer read Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 09/55] KVM: PPC: Book3S HV P9: Use large decrementer for HDEC Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 10/55] KVM: PPC: Book3S HV P9: Reduce mftb per guest entry/exit Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 11/55] powerpc/time: add API for KVM to re-arm the host timer/decrementer Nicholas Piggin
2021-08-05 7:22 ` Christophe Leroy
2021-08-06 10:30 ` Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 12/55] KVM: PPC: Book3S HV: POWER10 enable HAIL when running radix guests Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 13/55] powerpc/64s: Keep AMOR SPR a constant ~0 at runtime Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 14/55] KVM: PPC: Book3S HV: Don't always save PMU for guest capable of nesting Nicholas Piggin
2021-08-06 7:34 ` Michael Ellerman
2021-08-06 10:32 ` Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 15/55] powerpc/64s: Always set PMU control registers to frozen/disabled when not in use Nicholas Piggin
2021-07-26 3:49 ` [PATCH v1 16/55] powerpc/64s: Implement PMU override command line option Nicholas Piggin
2021-08-06 7:45 ` Madhavan Srinivasan
2021-08-06 10:38 ` Nicholas Piggin
2021-08-11 12:58 ` Madhavan Srinivasan
2021-08-06 9:40 ` Athira Rajeev
2021-08-06 10:42 ` Nicholas Piggin
2021-08-11 10:54 ` Athira Rajeev
2021-07-26 3:49 ` [PATCH v1 17/55] KVM: PPC: Book3S HV P9: Implement PMU save/restore in C Nicholas Piggin
2021-08-09 3:15 ` Athira Rajeev
2021-08-13 4:24 ` Nicholas Piggin
2021-08-14 7:24 ` Athira Rajeev
2021-07-26 3:49 ` [PATCH v1 18/55] KVM: PPC: Book3S HV P9: Factor PMU save/load into context switch functions Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 19/55] KVM: PPC: Book3S HV P9: Demand fault PMU SPRs when marked not inuse Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 20/55] KVM: PPC: Book3S HV P9: Factor out yield_count increment Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 21/55] KVM: PPC: Book3S HV: CTRL SPR does not require read-modify-write Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 22/55] KVM: PPC: Book3S HV P9: Move SPRG restore to restore_p9_host_os_sprs Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 23/55] KVM: PPC: Book3S HV P9: Reduce mtmsrd instructions required to save host SPRs Nicholas Piggin
2021-07-26 6:57 ` kernel test robot
2021-07-26 7:01 ` kernel test robot
2021-07-26 3:50 ` [PATCH v1 24/55] KVM: PPC: Book3S HV P9: Improve mtmsrd scheduling by delaying MSR[EE] disable Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 25/55] KVM: PPC: Book3S HV P9: Add kvmppc_stop_thread to match kvmppc_start_thread Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 26/55] KVM: PPC: Book3S HV: Change dec_expires to be relative to guest timebase Nicholas Piggin
2021-08-07 23:17 ` Michael Ellerman [this message]
2021-07-26 3:50 ` [PATCH v1 27/55] KVM: PPC: Book3S HV P9: Move TB updates Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 28/55] KVM: PPC: Book3S HV P9: Optimise timebase reads Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 29/55] KVM: PPC: Book3S HV P9: Avoid SPR scoreboard stalls Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 30/55] KVM: PPC: Book3S HV P9: Only execute mtSPR if the value changed Nicholas Piggin
2021-08-06 20:45 ` Fabiano Rosas
2021-07-26 3:50 ` [PATCH v1 31/55] KVM: PPC: Book3S HV P9: Juggle SPR switching around Nicholas Piggin
2021-08-06 20:46 ` Fabiano Rosas
2021-07-26 3:50 ` [PATCH v1 32/55] KVM: PPC: Book3S HV P9: Move vcpu register save/restore into functions Nicholas Piggin
2021-08-06 20:49 ` Fabiano Rosas
2021-07-26 3:50 ` [PATCH v1 33/55] KVM: PPC: Book3S HV P9: Move host OS save/restore functions to built-in Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 34/55] KVM: PPC: Book3S HV P9: Move nested guest entry into its own function Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 35/55] KVM: PPC: Book3S HV P9: Move remaining SPR and MSR access into low level entry Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 36/55] KVM: PPC: Book3S HV P9: Implement TM fastpath for guest entry/exit Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 37/55] KVM: PPC: Book3S HV P9: Switch PMU to guest as late as possible Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 38/55] KVM: PPC: Book3S HV P9: Restrict DSISR canary workaround to processors that require Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 39/55] KVM: PPC: Book3S HV P9: More SPR speed improvements Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 40/55] KVM: PPC: Book3S HV P9: Demand fault EBB facility registers Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 41/55] KVM: PPC: Book3S HV P9: Demand fault TM " Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 42/55] KVM: PPC: Book3S HV P9: Use Linux SPR save/restore to manage some host SPRs Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 43/55] KVM: PPC: Book3S HV P9: Comment and fix MMU context switching code Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 44/55] KVM: PPC: Book3S HV P9: Test dawr_enabled() before saving host DAWR SPRs Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 45/55] KVM: PPC: Book3S HV P9: Don't restore PSSCR if not needed Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 46/55] KVM: PPC: Book3S HV P9: Avoid tlbsync sequence on radix guest exit Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 47/55] KVM: PPC: Book3S HV Nested: Avoid extra mftb() in nested entry Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 48/55] KVM: PPC: Book3S HV P9: Improve mfmsr performance on entry Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 49/55] KVM: PPC: Book3S HV P9: Optimise hash guest SLB saving Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 50/55] KVM: PPC: Book3S HV P9: Add unlikely annotation for !mmu_ready Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 51/55] KVM: PPC: Book3S HV P9: Avoid cpu_in_guest atomics on entry and exit Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 52/55] KVM: PPC: Book3S HV P9: Remove most of the vcore logic Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 53/55] KVM: PPC: Book3S HV P9: Tidy kvmppc_create_dtl_entry Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 54/55] KVM: PPC: Book3S HV P9: Stop using vc->dpdes Nicholas Piggin
2021-07-26 3:50 ` [PATCH v1 55/55] KVM: PPC: Book3S HV P9: Remove subcore HMI handling Nicholas Piggin
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