linux-kernel - [RFC PATCH v2 14/20] x86/kvm: Make kvm_async_pf_enabled __ro_after

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Message-Id: <20230720163056.2564824-15-vschneid@redhat.com>
Date:   Thu, 20 Jul 2023 17:30:50 +0100
From:   Valentin Schneider <vschneid@...hat.com>
To:     linux-kernel@...r.kernel.org, linux-trace-kernel@...r.kernel.org,
        linux-doc@...r.kernel.org, kvm@...r.kernel.org, linux-mm@...ck.org,
        bpf@...r.kernel.org, x86@...nel.org, rcu@...r.kernel.org,
        linux-kselftest@...r.kernel.org
Cc:     Steven Rostedt <rostedt@...dmis.org>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Jonathan Corbet <corbet@....net>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
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Subject: [RFC PATCH v2 14/20] x86/kvm: Make kvm_async_pf_enabled __ro_after_init

objtool now warns about it:

  vmlinux.o: warning: objtool: exc_page_fault+0x2a: Non __ro_after_init static key "kvm_async_pf_enabled" in .noinstr section

The key can only be enabled (and not disabled) in the __init function
kvm_guest_init(), so mark it as __ro_after_init.

Signed-off-by: Valentin Schneider <vschneid@...hat.com>
---
 arch/x86/kernel/kvm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 1cceac5984daa..319460090a836 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -44,7 +44,7 @@
 #include <asm/svm.h>
 #include <asm/e820/api.h>
 
-DEFINE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
+DEFINE_STATIC_KEY_FALSE_RO(kvm_async_pf_enabled);
 
 static int kvmapf = 1;
 
-- 
2.31.1