diff options
author | Michael Roth <michael.roth@amd.com> | 2022-02-09 12:10:00 -0600 |
---|---|---|
committer | Borislav Petkov <bp@suse.de> | 2022-04-06 13:02:13 +0200 |
commit | 950d00558a920227b5703d1fcc4751cfe03853cd (patch) | |
tree | 6ae8f4472649d90a935b7d42b3f26277d898f2cd /arch/x86 | |
parent | 176db622573f028f85221873ea4577e096785315 (diff) | |
download | linux-950d00558a920227b5703d1fcc4751cfe03853cd.tar.bz2 |
x86/boot: Use MSR read/write helpers instead of inline assembly
Update all C code to use the new boot_rdmsr()/boot_wrmsr() helpers
instead of relying on inline assembly.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220307213356.2797205-7-brijesh.singh@amd.com
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/boot/compressed/sev.c | 17 | ||||
-rw-r--r-- | arch/x86/boot/cpucheck.c | 30 |
2 files changed, 22 insertions, 25 deletions
diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c index 28bcf04c022e..4e82101b7d13 100644 --- a/arch/x86/boot/compressed/sev.c +++ b/arch/x86/boot/compressed/sev.c @@ -22,6 +22,7 @@ #include <asm/svm.h> #include "error.h" +#include "../msr.h" struct ghcb boot_ghcb_page __aligned(PAGE_SIZE); struct ghcb *boot_ghcb; @@ -56,23 +57,19 @@ static unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx) static inline u64 sev_es_rd_ghcb_msr(void) { - unsigned long low, high; + struct msr m; - asm volatile("rdmsr" : "=a" (low), "=d" (high) : - "c" (MSR_AMD64_SEV_ES_GHCB)); + boot_rdmsr(MSR_AMD64_SEV_ES_GHCB, &m); - return ((high << 32) | low); + return m.q; } static inline void sev_es_wr_ghcb_msr(u64 val) { - u32 low, high; + struct msr m; - low = val & 0xffffffffUL; - high = val >> 32; - - asm volatile("wrmsr" : : "c" (MSR_AMD64_SEV_ES_GHCB), - "a"(low), "d" (high) : "memory"); + m.q = val; + boot_wrmsr(MSR_AMD64_SEV_ES_GHCB, &m); } static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) diff --git a/arch/x86/boot/cpucheck.c b/arch/x86/boot/cpucheck.c index e1478d32de1a..fed8d13ce252 100644 --- a/arch/x86/boot/cpucheck.c +++ b/arch/x86/boot/cpucheck.c @@ -27,6 +27,7 @@ #include <asm/required-features.h> #include <asm/msr-index.h> #include "string.h" +#include "msr.h" static u32 err_flags[NCAPINTS]; @@ -130,12 +131,11 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr) /* If this is an AMD and we're only missing SSE+SSE2, try to turn them on */ - u32 ecx = MSR_K7_HWCR; - u32 eax, edx; + struct msr m; - asm("rdmsr" : "=a" (eax), "=d" (edx) : "c" (ecx)); - eax &= ~(1 << 15); - asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx)); + boot_rdmsr(MSR_K7_HWCR, &m); + m.l &= ~(1 << 15); + boot_wrmsr(MSR_K7_HWCR, &m); get_cpuflags(); /* Make sure it really did something */ err = check_cpuflags(); @@ -145,28 +145,28 @@ int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr) /* If this is a VIA C3, we might have to enable CX8 explicitly */ - u32 ecx = MSR_VIA_FCR; - u32 eax, edx; + struct msr m; - asm("rdmsr" : "=a" (eax), "=d" (edx) : "c" (ecx)); - eax |= (1<<1)|(1<<7); - asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx)); + boot_rdmsr(MSR_VIA_FCR, &m); + m.l |= (1 << 1) | (1 << 7); + boot_wrmsr(MSR_VIA_FCR, &m); set_bit(X86_FEATURE_CX8, cpu.flags); err = check_cpuflags(); } else if (err == 0x01 && is_transmeta()) { /* Transmeta might have masked feature bits in word 0 */ - u32 ecx = 0x80860004; - u32 eax, edx; + struct msr m, m_tmp; u32 level = 1; - asm("rdmsr" : "=a" (eax), "=d" (edx) : "c" (ecx)); - asm("wrmsr" : : "a" (~0), "d" (edx), "c" (ecx)); + boot_rdmsr(0x80860004, &m); + m_tmp = m; + m_tmp.l = ~0; + boot_wrmsr(0x80860004, &m_tmp); asm("cpuid" : "+a" (level), "=d" (cpu.flags[0]) : : "ecx", "ebx"); - asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx)); + boot_wrmsr(0x80860004, &m); err = check_cpuflags(); } else if (err == 0x01 && |