On 11.02.2022 16:25, Norbert Manthey wrote: > When re-identifying CPU data, we might use uninitialized data when > checking for the cache line property to adapt the cache > alignment. The data that depends on this uninitialized read is > currently not forwarded. > > To avoid problems in the future, initialize the data cpuinfo > structure before re-identifying the CPU again. > > The trace to hit the uninitialized read reported by Coverity is: > > bool recheck_cpu_features(unsigned int cpu) > ... > struct cpuinfo_x86 c; > ... > identify_cpu(&c); > > void identify_cpu(struct cpuinfo_x86 *c) > ... > generic_identify(c) > > static void generic_identify(struct cpuinfo_x86 *c) > ... > if (this_cpu->c_early_init) > this_cpu->c_early_init(c); // which is early_init_intel > > static void early_init_intel(struct cpuinfo_x86 *c) > ... > if (c->x86 == 15 && c->x86_cache_alignment == 64) > c->x86_cache_alignment = 128; > > This bug was discovered and resolved using Coverity Static Analysis > Security Testing (SAST) by Synopsys, Inc. > > Signed-off-by: Norbert Manthey <nmant...@amazon.de>
Acked-by: Jan Beulich <jbeul...@suse.com>
