6.6-stable review patch. If anyone has any objections, please let me know.
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From: Pawan Gupta pawan.kumar.gupta@linux.intel.com
[ Upstream commit 9f85fdb9fc5a1bd308a10a0a7d7e34f2712ba58b ]
The purpose of the warning is to prevent an unexpected change to the return thunk mitigation. However, there are legitimate cases where the return thunk is intentionally set more than once. For example, ITS and SRSO both can set the return thunk after retbleed has set it. In both the cases retbleed is still mitigated.
Replace the warning with an info about the active return thunk.
Suggested-by: Borislav Petkov bp@alien8.de Signed-off-by: Pawan Gupta pawan.kumar.gupta@linux.intel.com Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Link: https://lore.kernel.org/20250611-eibrs-fix-v4-3-5ff86cac6c61@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kernel/cpu/bugs.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index c4d5ac99c6af..332c6f24280d 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -71,10 +71,9 @@ void (*x86_return_thunk)(void) __ro_after_init = __x86_return_thunk;
static void __init set_return_thunk(void *thunk) { - if (x86_return_thunk != __x86_return_thunk) - pr_warn("x86/bugs: return thunk changed\n"); - x86_return_thunk = thunk; + + pr_info("active return thunk: %ps\n", thunk); }
/* Update SPEC_CTRL MSR and its cached copy unconditionally */