From: Paul Mackerras <pau...@ozlabs.org>
commit 1b28d5531e446a87bbefa5ced191c4cbd316576c upstream.
Commit 3309bec85e60 ("KVM: PPC: Book3S HV: Fix lockdep warning when
entering the guest") moved calls to trace_hardirqs_{on,off} in the
entry path used for HPT guests. Similar code exists in the new
streamlined entry path used for radix guests on POWER9. This makes
the same change there, so as to avoid lockdep warnings such as this:
[ 228.686461] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
[ 228.686480] WARNING: CPU: 116 PID: 3803 at ../kernel/locking/lockdep.c:4219
check_flags.part.23+0x21c/0x270
[ 228.686544] Modules linked in: vhost_net vhost xt_CHECKSUM iptable_mangle
xt_MASQUERADE iptable_nat nf_nat
+xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ipt_REJECT
nf_reject_ipv4 tun bridge stp llc ebtable_filter
+ebtables ip6table_filter ip6_tables iptable_filter fuse kvm_hv kvm at24
ipmi_powernv regmap_i2c ipmi_devintf
+uio_pdrv_genirq ofpart ipmi_msghandler uio powernv_flash mtd ibmpowernv
opal_prd ip_tables ext4 mbcache jbd2 btrfs
+zstd_decompress zstd_compress raid10 raid456 async_raid6_recov async_memcpy
async_pq async_xor async_tx libcrc32c xor
+raid6_pq raid1 raid0 ses sd_mod enclosure scsi_transport_sas ast i2c_opal
i2c_algo_bit drm_kms_helper syscopyarea
+sysfillrect sysimgblt fb_sys_fops ttm drm i40e e1000e cxl aacraid tg3
drm_panel_orientation_quirks i2c_core
[ 228.686859] CPU: 116 PID: 3803 Comm: qemu-system-ppc Kdump: loaded Not
tainted 5.2.0-rc1-xive+ #42
[ 228.686911] NIP: c0000000001b394c LR: c0000000001b3948 CTR: c000000000bfad20
[ 228.686963] REGS: c000200cdb50f570 TRAP: 0700 Not tainted
(5.2.0-rc1-xive+)
[ 228.687001] MSR: 9000000002823033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE> CR:
48222222 XER: 20040000
[ 228.687060] CFAR: c000000000116db0 IRQMASK: 1
[ 228.687060] GPR00: c0000000001b3948 c000200cdb50f800 c0000000015e7600
000000000000002e
[ 228.687060] GPR04: 0000000000000001 c0000000001c71a0 000000006e655f73
72727563284e4f5f
[ 228.687060] GPR08: 0000200e60680000 0000000000000000 c000200cdb486180
0000000000000000
[ 228.687060] GPR12: 0000000000002000 c000200fff61a680 0000000000000000
00007fffb75c0000
[ 228.687060] GPR16: 0000000000000000 0000000000000000 c0000000017d6900
c000000001124900
[ 228.687060] GPR20: 0000000000000074 c008000006916f68 0000000000000074
0000000000000074
[ 228.687060] GPR24: ffffffffffffffff ffffffffffffffff 0000000000000003
c000200d4b600000
[ 228.687060] GPR28: c000000001627e58 c000000001489908 c000000001627e58
c000000002304de0
[ 228.687377] NIP [c0000000001b394c] check_flags.part.23+0x21c/0x270
[ 228.687415] LR [c0000000001b3948] check_flags.part.23+0x218/0x270
[ 228.687466] Call Trace:
[ 228.687488] [c000200cdb50f800] [c0000000001b3948]
check_flags.part.23+0x218/0x270 (unreliable)
[ 228.687542] [c000200cdb50f870] [c0000000001b6548]
lock_is_held_type+0x188/0x1c0
[ 228.687595] [c000200cdb50f8d0] [c0000000001d939c]
rcu_read_lock_sched_held+0xdc/0x100
[ 228.687646] [c000200cdb50f900] [c0000000001dd704]
rcu_note_context_switch+0x304/0x340
[ 228.687701] [c000200cdb50f940] [c0080000068fcc58]
kvmhv_run_single_vcpu+0xdb0/0x1120 [kvm_hv]
[ 228.687756] [c000200cdb50fa20] [c0080000068fd5b0]
kvmppc_vcpu_run_hv+0x5e8/0xe40 [kvm_hv]
[ 228.687816] [c000200cdb50faf0] [c0080000071797dc] kvmppc_vcpu_run+0x34/0x48
[kvm]
[ 228.687863] [c000200cdb50fb10] [c0080000071755dc]
kvm_arch_vcpu_ioctl_run+0x244/0x420 [kvm]
[ 228.687916] [c000200cdb50fba0] [c008000007165ccc] kvm_vcpu_ioctl+0x424/0x838
[kvm]
[ 228.687957] [c000200cdb50fd10] [c000000000433a24] do_vfs_ioctl+0xd4/0xcd0
[ 228.687995] [c000200cdb50fdb0] [c000000000434724] ksys_ioctl+0x104/0x120
[ 228.688033] [c000200cdb50fe00] [c000000000434768] sys_ioctl+0x28/0x80
[ 228.688072] [c000200cdb50fe20] [c00000000000b888] system_call+0x5c/0x70
[ 228.688109] Instruction dump:
[ 228.688142] 4bf6342d 60000000 0fe00000 e8010080 7c0803a6 4bfffe60 3c82ff87
3c62ff87
[ 228.688196] 388472d0 3863d738 4bf63405 60000000 <0fe00000> 4bffff4c 3c82ff87
3c62ff87
[ 228.688251] irq event stamp: 205
[ 228.688287] hardirqs last enabled at (205): [<c0080000068fc1b4>]
kvmhv_run_single_vcpu+0x30c/0x1120 [kvm_hv]
[ 228.688344] hardirqs last disabled at (204): [<c0080000068fbff0>]
kvmhv_run_single_vcpu+0x148/0x1120 [kvm_hv]
[ 228.688412] softirqs last enabled at (180): [<c000000000c0b2ac>]
__do_softirq+0x4ac/0x5d4
[ 228.688464] softirqs last disabled at (169): [<c000000000122aa8>]
irq_exit+0x1f8/0x210
[ 228.688513] ---[ end trace eb16f6260022a812 ]---
[ 228.688548] possible reason: unannotated irqs-off.
[ 228.688571] irq event stamp: 205
[ 228.688607] hardirqs last enabled at (205): [<c0080000068fc1b4>]
kvmhv_run_single_vcpu+0x30c/0x1120 [kvm_hv]
[ 228.688664] hardirqs last disabled at (204): [<c0080000068fbff0>]
kvmhv_run_single_vcpu+0x148/0x1120 [kvm_hv]
[ 228.688719] softirqs last enabled at (180): [<c000000000c0b2ac>]
__do_softirq+0x4ac/0x5d4
[ 228.688758] softirqs last disabled at (169): [<c000000000122aa8>]
irq_exit+0x1f8/0x210
Cc: sta...@vger.kernel.org # v4.20+
Fixes: 95a6432ce903 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on
P9 for radix guests")
Signed-off-by: Paul Mackerras <pau...@ozlabs.org>
Reviewed-by: Cédric Le Goater <c...@kaod.org>
Tested-by: Cédric Le Goater <c...@kaod.org>
Signed-off-by: Paul Mackerras <pau...@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
arch/powerpc/kvm/book3s_hv.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4048,16 +4048,20 @@ int kvmhv_run_single_vcpu(struct kvm_run
if (cpu_has_feature(CPU_FTR_HVMODE))
kvmppc_radix_check_need_tlb_flush(kvm, pcpu, nested);
- trace_hardirqs_on();
guest_enter_irqoff();
srcu_idx = srcu_read_lock(&kvm->srcu);
this_cpu_disable_ftrace();
+ /* Tell lockdep that we're about to enable interrupts */
+ trace_hardirqs_on();
+
trap = kvmhv_p9_guest_entry(vcpu, time_limit, lpcr);
vcpu->arch.trap = trap;
+ trace_hardirqs_off();
+
this_cpu_enable_ftrace();
srcu_read_unlock(&kvm->srcu, srcu_idx);
@@ -4067,7 +4071,6 @@ int kvmhv_run_single_vcpu(struct kvm_run
isync();
}
- trace_hardirqs_off();
set_irq_happened(trap);
kvmppc_set_host_core(pcpu);
