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author | Peter Zijlstra <peterz@infradead.org> | 2019-07-11 13:40:55 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2019-07-17 23:17:37 +0200 |
commit | 55aedddb6149ab71bec9f050846855113977b033 (patch) | |
tree | d9154c2a76eea96bdb139f1862a6f0ec72613a2d /arch/x86/include/asm/paravirt.h | |
parent | 406de552c2be6ded524c75d14a73cf7f027f587e (diff) | |
download | linux-stable-55aedddb6149ab71bec9f050846855113977b033.tar.gz linux-stable-55aedddb6149ab71bec9f050846855113977b033.tar.bz2 linux-stable-55aedddb6149ab71bec9f050846855113977b033.zip |
x86/paravirt: Make read_cr2() CALLEE_SAVE
The one paravirt read_cr2() implementation (Xen) is actually quite trivial
and doesn't need to clobber anything other than the return register.
Making read_cr2() CALLEE_SAVE avoids all the PUSH/POP nonsense and allows
more convenient use from assembly.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: bp@alien8.de
Cc: rostedt@goodmis.org
Cc: luto@kernel.org
Cc: torvalds@linux-foundation.org
Cc: hpa@zytor.com
Cc: dave.hansen@linux.intel.com
Cc: zhe.he@windriver.com
Cc: joel@joelfernandes.org
Cc: devel@etsukata.com
Link: https://lkml.kernel.org/r/20190711114335.887392493@infradead.org
Diffstat (limited to 'arch/x86/include/asm/paravirt.h')
-rw-r--r-- | arch/x86/include/asm/paravirt.h | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index c25c38a05c1c..5135282683d4 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -116,7 +116,7 @@ static inline void write_cr0(unsigned long x) static inline unsigned long read_cr2(void) { - return PVOP_CALL0(unsigned long, mmu.read_cr2); + return PVOP_CALLEE0(unsigned long, mmu.read_cr2); } static inline void write_cr2(unsigned long x) @@ -909,13 +909,7 @@ extern void default_banner(void); ANNOTATE_RETPOLINE_SAFE; \ call PARA_INDIRECT(pv_ops+PV_CPU_swapgs); \ ) -#endif - -#define GET_CR2_INTO_RAX \ - ANNOTATE_RETPOLINE_SAFE; \ - call PARA_INDIRECT(pv_ops+PV_MMU_read_cr2); -#ifdef CONFIG_PARAVIRT_XXL #define USERGS_SYSRET64 \ PARA_SITE(PARA_PATCH(PV_CPU_usergs_sysret64), \ ANNOTATE_RETPOLINE_SAFE; \ @@ -929,9 +923,19 @@ extern void default_banner(void); call PARA_INDIRECT(pv_ops+PV_IRQ_save_fl); \ PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);) #endif -#endif +#endif /* CONFIG_PARAVIRT_XXL */ +#endif /* CONFIG_X86_64 */ + +#ifdef CONFIG_PARAVIRT_XXL + +#define GET_CR2_INTO_AX \ + PARA_SITE(PARA_PATCH(PV_MMU_read_cr2), \ + ANNOTATE_RETPOLINE_SAFE; \ + call PARA_INDIRECT(pv_ops+PV_MMU_read_cr2); \ + ) + +#endif /* CONFIG_PARAVIRT_XXL */ -#endif /* CONFIG_X86_32 */ #endif /* __ASSEMBLY__ */ #else /* CONFIG_PARAVIRT */ |