x86/microcode/AMD: Fix a -Wsometimes-uninitialized clang false positive

Initialize equiv_id in order to shut up:

  arch/x86/kernel/cpu/microcode/amd.c:714:6: warning: variable 'equiv_id' is \
  used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
        if (x86_family(bsp_cpuid_1_eax) < 0x17) {
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

because clang doesn't do interprocedural analysis for warnings to see
that this variable won't be used uninitialized.

Fixes: 94838d230a6c ("x86/microcode/AMD: Use the family,model,stepping encoded in the patch ID")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202407291815.gJBST0P3-lkp@intel.com/
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>

diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 1f5d36f92b8a2850fa44f37c0437f57c3115f496..f63b051f25a0a982747045b0921eacccc4a0fe68 100644 (file)
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -703,7 +703,7 @@ static struct ucode_patch *find_patch(unsigned int cpu)
 {
        struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
        u32 rev, dummy __always_unused;
-       u16 equiv_id;
+       u16 equiv_id = 0;
 
        /* fetch rev if not populated yet: */
        if (!uci->cpu_sig.rev) {