Patrick Georgi has submitted this change and it was merged. ( https://review.coreboot.org/c/coreboot/+/31527 )
Change subject: cpu/x86/mtrr/mtrr.c:Avoid static scan false positive ......................................................................
cpu/x86/mtrr/mtrr.c:Avoid static scan false positive
Static scan does not know the contents of the fixed MTRR descriptor, so it has no way to eval the result for variable num_ranges. If num_ranges is less or equal to 0, the for loop will not be entered, and the values of fixed_msrs will not be set. Asserting that num_ranges is greater than 0 ensures the loop enters at least once.
BUG=b:112253891 TEST=build grunt
Change-Id: Ieec0ac432c745bde4b1700539c266625da6cfd77 Signed-off-by: Richard Spiegel richard.spiegel@silverbackltd.com Reviewed-on: https://review.coreboot.org/c/31527 Tested-by: build bot (Jenkins) no-reply@coreboot.org Reviewed-by: Martin Roth martinroth@google.com --- M src/cpu/x86/mtrr/mtrr.c 1 file changed, 2 insertions(+), 0 deletions(-)
Approvals: build bot (Jenkins): Verified Martin Roth: Looks good to me, approved
diff --git a/src/cpu/x86/mtrr/mtrr.c b/src/cpu/x86/mtrr/mtrr.c index 23473df..249d631 100644 --- a/src/cpu/x86/mtrr/mtrr.c +++ b/src/cpu/x86/mtrr/mtrr.c @@ -36,6 +36,7 @@ #include <arch/acpi.h> #include <memrange.h> #include <cpu/amd/mtrr.h> +#include <assert.h> #if IS_ENABLED(CONFIG_X86_AMD_FIXED_MTRRS) #define MTRR_FIXED_WRBACK_BITS (MTRR_READ_MEM | MTRR_WRITE_MEM) #else @@ -331,6 +332,7 @@
desc = &fixed_mtrr_desc[i]; num_ranges = (desc->end - desc->begin) / desc->step; + ASSERT(num_ranges > 0); for (j = 0; j < num_ranges; j += RANGES_PER_FIXED_MTRR) { msr_index[msr_num] = desc->msr_index_base + (j / RANGES_PER_FIXED_MTRR);