diff options
| author | Visa Hankala <visa@cvs.openbsd.org> | 2019-08-21 16:14:35 +0000 |
|---|---|---|
| committer | Visa Hankala <visa@cvs.openbsd.org> | 2019-08-21 16:14:35 +0000 |
| commit | 8cb1a48eef9deacb41419fd5c2bf34a9e1665667 (patch) | |
| tree | 739549f5371c619d7e5a9957ae1cb0e6f8688cf7 /sys/arch/mips64/include | |
| parent | 4f74f46798e48f16726d9230265d67293e730884 (diff) | |
Fix a race in invalidation of remote TLB entries.
If a CPU updates a pmap concurrently with the activation of that pmap
on another CPU, invalidation of TLB entries might be incomplete.
It is also possible that a CPU altogether stops updating its TLB.
Prevent the race by synchronizing pmap activations and logic that
determines where to send TLB invalidation IPIs.
To avoid mutex wait without ability to process IPIs, the context switch
code is adjusted to call pmap_activate() with interrupts enabled.
In practice, interrupts up to IPL_SCHED are still disabled on context
switch.
Diffstat (limited to 'sys/arch/mips64/include')
| -rw-r--r-- | sys/arch/mips64/include/pmap.h | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/sys/arch/mips64/include/pmap.h b/sys/arch/mips64/include/pmap.h index df76f26e314..b38f09aa01f 100644 --- a/sys/arch/mips64/include/pmap.h +++ b/sys/arch/mips64/include/pmap.h @@ -1,4 +1,4 @@ -/* $OpenBSD: pmap.h,v 1.47 2018/10/22 17:31:25 krw Exp $ */ +/* $OpenBSD: pmap.h,v 1.48 2019/08/21 16:14:34 visa Exp $ */ /* * Copyright (c) 1987 Carnegie-Mellon University @@ -117,6 +117,7 @@ struct pmap_asid_info { */ typedef struct pmap { struct mutex pm_mtx; /* pmap lock */ + struct mutex pm_swmtx; /* pmap switch lock */ int pm_count; /* pmap reference count */ struct pmap_statistics pm_stats; /* pmap statistics */ struct segtab *pm_segtab; /* pointers to pages of PTEs */ |