From: Boris Ostrovsky Date: Sun, 18 Dec 2016 16:44:14 +0000 (+0100) Subject: x86/microcode/AMD: Use native_cpuid() in load_ucode_amd_bsp() X-Git-Tag: v4.10-rc1~12^2~20 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=2b4c91569a40c4512ea1b413e0c817d179ce9868;p=linux.git x86/microcode/AMD: Use native_cpuid() in load_ucode_amd_bsp() When CONFIG_PARAVIRT is selected, cpuid() becomes a call. Since for 32-bit kernels load_ucode_amd_bsp() is executed before paging is enabled the call cannot be completed (as kernel virtual addresses are not reachable yet). Use native_cpuid() instead which is an asm wrapper for the CPUID instruction. Signed-off-by: Boris Ostrovsky Signed-off-by: Borislav Petkov Cc: Jürgen Gross Link: http://lkml.kernel.org/r/1481906392-3847-1-git-send-email-boris.ostrovsky@oracle.com Link: http://lkml.kernel.org/r/20161218164414.9649-5-bp@alien8.de Signed-off-by: Thomas Gleixner --- diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index dc80acfa922d..6a31e2691f3a 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -301,6 +301,7 @@ static bool get_builtin_microcode(struct cpio_data *cp, unsigned int family) void __init load_ucode_amd_bsp(unsigned int family) { struct ucode_cpu_info *uci; + u32 eax, ebx, ecx, edx; struct cpio_data cp; const char *path; bool use_pa; @@ -322,7 +323,10 @@ void __init load_ucode_amd_bsp(unsigned int family) return; /* Get BSP's CPUID.EAX(1), needed in load_microcode_amd() */ - uci->cpu_sig.sig = cpuid_eax(1); + eax = 1; + ecx = 0; + native_cpuid(&eax, &ebx, &ecx, &edx); + uci->cpu_sig.sig = eax; apply_microcode_early_amd(cp.data, cp.size, true, NULL); }