linux-kernel - [PATCH 06/10] x86/fpu: Log XSAVE disablement consistently

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250416021720.12305-7-chang.seok.bae@intel.com>
Date: Tue, 15 Apr 2025 19:16:56 -0700
From: "Chang S. Bae" <chang.seok.bae@...el.com>
To: mingo@...hat.com
Cc: linux-kernel@...r.kernel.org,
	x86@...nel.org,
	tglx@...utronix.de,
	bp@...en8.de,
	dave.hansen@...ux.intel.com,
	chang.seok.bae@...el.com
Subject: [PATCH 06/10] x86/fpu: Log XSAVE disablement consistently

Not all paths that lead to fpu__init_disable_system_xstate() currently
emit a message indicating that XSAVE has been disabled. Move the print
statement into the function to ensure the message in all cases.

Suggested-by: Dave Hansen <dave.hansen@...ux.intel.com>
Signed-off-by: Chang S. Bae <chang.seok.bae@...el.com>
Link: https://lore.kernel.org/lkml/d6d19e39-2749-4d45-aeab-a209a0ecba17@intel.com
---
New patch for following up patch 3.
---
 arch/x86/kernel/fpu/xstate.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 2ac1fc182273..8b14c9d3a1df 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -751,6 +751,8 @@ static int __init init_xstate_size(void)
  */
 static void __init fpu__init_disable_system_xstate(unsigned int legacy_size)
 {
+	pr_info("x86/fpu: XSAVE disabled\n");
+
 	fpu_kernel_cfg.max_features = 0;
 	cr4_clear_bits(X86_CR4_OSXSAVE);
 	setup_clear_cpu_cap(X86_FEATURE_XSAVE);
@@ -821,7 +823,7 @@ void __init fpu__init_system_xstate(unsigned int legacy_size)
 		 * This is a problematic CPU configuration where two
 		 * conflicting state components are both enumerated.
 		 */
-		pr_err("x86/fpu: Both APX/MPX present in the CPU's xstate features: 0x%llx, disabling XSAVE.\n",
+		pr_err("x86/fpu: Both APX/MPX present in the CPU's xstate features: 0x%llx.\n",
 		       fpu_kernel_cfg.max_features);
 		goto out_disable;
 	}
@@ -900,7 +902,7 @@ void __init fpu__init_system_xstate(unsigned int legacy_size)
 	init_fpstate.xfeatures		= fpu_kernel_cfg.default_features;
 
 	if (init_fpstate.size > sizeof(init_fpstate.regs)) {
-		pr_warn("x86/fpu: init_fpstate buffer too small (%zu < %d), disabling XSAVE\n",
+		pr_warn("x86/fpu: init_fpstate buffer too small (%zu < %d)\n",
 			sizeof(init_fpstate.regs), init_fpstate.size);
 		goto out_disable;
 	}
@@ -912,7 +914,7 @@ void __init fpu__init_system_xstate(unsigned int legacy_size)
 	 * xfeatures mask.
 	 */
 	if (xfeatures != fpu_kernel_cfg.max_features) {
-		pr_err("x86/fpu: xfeatures modified from 0x%016llx to 0x%016llx during init, disabling XSAVE\n",
+		pr_err("x86/fpu: xfeatures modified from 0x%016llx to 0x%016llx during init\n",
 		       xfeatures, fpu_kernel_cfg.max_features);
 		goto out_disable;
 	}
-- 
2.45.2