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9249bcdea0
The boot_{rdmsr,wrmsr}() helpers are *just* the barebones MSR access
functionality, without any tracing or exception handling glue as it is done in
kernel proper.
Move these helpers to asm/shared/msr.h and rename to raw_{rdmsr,wrmsr}() to
indicate what they are.
[ bp: Correct the reason why those helpers exist. I should've caught that in
the original patch that added them:
176db62257 ("x86/boot: Introduce helpers for MSR reads/writes"
but oh well...
- fixup include path delimiters to <> ]
Signed-off-by: John Allen <john.allen@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://patch.msgid.link/all/20250924200852.4452-2-john.allen@amd.com
31 lines
680 B
C
31 lines
680 B
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_X86_SHARED_MSR_H
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#define _ASM_X86_SHARED_MSR_H
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struct msr {
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union {
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struct {
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u32 l;
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u32 h;
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};
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u64 q;
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};
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};
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/*
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* The kernel proper already defines rdmsr()/wrmsr(), but they are not for the
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* boot kernel since they rely on tracepoint/exception handling infrastructure
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* that's not available here.
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*/
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static inline void raw_rdmsr(unsigned int reg, struct msr *m)
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{
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asm volatile("rdmsr" : "=a" (m->l), "=d" (m->h) : "c" (reg));
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}
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static inline void raw_wrmsr(unsigned int reg, const struct msr *m)
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{
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asm volatile("wrmsr" : : "c" (reg), "a"(m->l), "d" (m->h) : "memory");
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}
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#endif /* _ASM_X86_SHARED_MSR_H */
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