x86: Avoid integer truncation with large cache sizes (bug 32470)

Some hypervisors report 1 TiB L3 cache size.  This results
in some variables incorrectly getting zeroed, causing crashes
in memcpy/memmove because invariants are violated.
This commit is contained in:
Florian Weimer 2024-12-17 18:12:03 +01:00
parent 77e921bc61
commit 61c3450db9

View file

@ -1021,11 +1021,11 @@ dl_init_cacheinfo (struct cpu_features *cpu_features)
non_temporal_threshold = maximum_non_temporal_threshold;
/* NB: The REP MOVSB threshold must be greater than VEC_SIZE * 8. */
unsigned int minimum_rep_movsb_threshold;
unsigned long int minimum_rep_movsb_threshold;
/* NB: The default REP MOVSB threshold is 4096 * (VEC_SIZE / 16) for
VEC_SIZE == 64 or 32. For VEC_SIZE == 16, the default REP MOVSB
threshold is 2048 * (VEC_SIZE / 16). */
unsigned int rep_movsb_threshold;
unsigned long int rep_movsb_threshold;
if (CPU_FEATURE_USABLE_P (cpu_features, AVX512F)
&& !CPU_FEATURE_PREFERRED_P (cpu_features, Prefer_No_AVX512))
{