diff options
| author | Konstantin Belousov <kib@FreeBSD.org> | 2026-01-19 11:55:36 +0000 |
|---|---|---|
| committer | Konstantin Belousov <kib@FreeBSD.org> | 2026-01-19 16:20:37 +0000 |
| commit | 709a53c8b20b5770f7e2f117d4799b5617479976 (patch) | |
| tree | 1a5f892c394a4c46f0ec8fc1f5d2d67cf4c41197 | |
| parent | ad5e3cb950344f9822dbbd90f5ac7c256f97fa4c (diff) | |
x86/local_apic.c: Properly calculate the number of LVT entries
First, the CMCI entry index is APIC_LVT_MAX, so it was excluded
unconditionall [1].
Second, the number of entries is reported by the version register, and
we must not access past the last reported entry.
Reported by: olivier [1]
Fixes: 11f954b021a1aadde1d03d40ed5d6b529e14da98
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D54773
| -rw-r--r-- | sys/x86/include/apicreg.h | 7 | ||||
| -rw-r--r-- | sys/x86/x86/local_apic.c | 7 |
2 files changed, 11 insertions, 3 deletions
diff --git a/sys/x86/include/apicreg.h b/sys/x86/include/apicreg.h index 1252647fbab3..4cc9cabdad9e 100644 --- a/sys/x86/include/apicreg.h +++ b/sys/x86/include/apicreg.h @@ -439,7 +439,12 @@ typedef struct IOAPIC ioapic_t; #define APIC_EXTF_SEIO_CAP 0x00000002 #define APIC_EXTF_IER_CAP 0x00000001 -/* LVT table indices */ +/* + * LVT table indices. + * Must be ordered following the appearance of the LVT entries in + * series the LAPIC versions, which is reported by LAPIC_VERSION + * MAXLVT field. + */ #define APIC_LVT_LINT0 0 #define APIC_LVT_LINT1 1 #define APIC_LVT_TIMER 2 diff --git a/sys/x86/x86/local_apic.c b/sys/x86/x86/local_apic.c index 68f42c9eed0b..b444142d5481 100644 --- a/sys/x86/x86/local_apic.c +++ b/sys/x86/x86/local_apic.c @@ -819,9 +819,12 @@ lapic_early_mask_vec(const struct lvt *l) static void lapic_early_mask_vecs(void) { - int elvt_count, i; + int elvt_count, lvts_count, i; + uint32_t version; - for (i = 0; i < APIC_LVT_MAX; i++) + version = lapic_read32(LAPIC_VERSION); + lvts_count = min(nitems(lvts), lapic_maxlvt(version) + 1); + for (i = 0; i < lvts_count; i++) lapic_early_mask_vec(&lvts[i]); elvt_count = amd_read_elvt_count(); |