From 0ef8047b737d7480a5d4c46d956e97c190f13050 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 29 Nov 2024 16:15:54 +0100 Subject: x86/static-call: provide a way to do very early static-call updates Add static_call_update_early() for updating static-call targets in very early boot. This will be needed for support of Xen guest type specific hypercall functions. This is part of XSA-466 / CVE-2024-53241. Reported-by: Andrew Cooper Signed-off-by: Juergen Gross Co-developed-by: Peter Zijlstra Co-developed-by: Josh Poimboeuf --- include/linux/static_call.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/static_call.h') diff --git a/include/linux/static_call.h b/include/linux/static_call.h index 141e6b176a1b..785980af8972 100644 --- a/include/linux/static_call.h +++ b/include/linux/static_call.h @@ -138,6 +138,7 @@ #ifdef CONFIG_HAVE_STATIC_CALL #include +extern int static_call_initialized; /* * Either @site or @tramp can be NULL. */ -- cgit v1.2.3 From 349f0086ba8b2a169877d21ff15a4d9da3a60054 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Wed, 18 Dec 2024 09:02:28 +0100 Subject: x86/static-call: fix 32-bit build In 32-bit x86 builds CONFIG_STATIC_CALL_INLINE isn't set, leading to static_call_initialized not being available. Define it as "0" in that case. Reported-by: Stephen Rothwell Fixes: 0ef8047b737d ("x86/static-call: provide a way to do very early static-call updates") Signed-off-by: Juergen Gross Acked-by: Peter Zijlstra (Intel) Signed-off-by: Linus Torvalds --- include/linux/static_call.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'include/linux/static_call.h') diff --git a/include/linux/static_call.h b/include/linux/static_call.h index 785980af8972..78a77a4ae0ea 100644 --- a/include/linux/static_call.h +++ b/include/linux/static_call.h @@ -138,7 +138,6 @@ #ifdef CONFIG_HAVE_STATIC_CALL #include -extern int static_call_initialized; /* * Either @site or @tramp can be NULL. */ @@ -161,6 +160,8 @@ extern void arch_static_call_transform(void *site, void *tramp, void *func, bool #ifdef CONFIG_HAVE_STATIC_CALL_INLINE +extern int static_call_initialized; + extern int __init static_call_init(void); extern void static_call_force_reinit(void); @@ -226,6 +227,8 @@ extern long __static_call_return0(void); #elif defined(CONFIG_HAVE_STATIC_CALL) +#define static_call_initialized 0 + static inline int static_call_init(void) { return 0; } #define DEFINE_STATIC_CALL(name, _func) \ @@ -282,6 +285,8 @@ extern long __static_call_return0(void); #else /* Generic implementation */ +#define static_call_initialized 0 + static inline int static_call_init(void) { return 0; } static inline long __static_call_return0(void) -- cgit v1.2.3