Merge branch 'x86/alternatives' into x86/core, to merge dependent commits

Prepare to resolve conflicts with an upstream series of fixes that conflict
with pending x86 changes:

  6f5bf947bab0 Merge tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 10 insertions, 3 deletions

diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index 98631c0e7a11..f786401ac15d 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -631,14 +631,21 @@ static bool get_desc(struct desc_struct *out, unsigned short sel)
 		/* Bits [15:3] contain the index of the desired entry. */
 		sel >>= 3;
 
-		mutex_lock(&current->active_mm->context.lock);
-		ldt = current->active_mm->context.ldt;
+		/*
+		 * If we're not in a valid context with a real (not just lazy)
+		 * user mm, then don't even try.
+		 */
+		if (!nmi_uaccess_okay())
+			return false;
+
+		mutex_lock(&current->mm->context.lock);
+		ldt = current->mm->context.ldt;
 		if (ldt && sel < ldt->nr_entries) {
 			*out = ldt->entries[sel];
 			success = true;
 		}
 
-		mutex_unlock(&current->active_mm->context.lock);
+		mutex_unlock(&current->mm->context.lock);
 
 		return success;
 	}