Re: [PATCH] x86/fred: Fix early boot failures on SEV-ES/SNP guests

On 2/5/2026 11:26 AM, Greg KH wrote:

On Thu, Feb 05, 2026 at 05:10:30AM +0000, Nikunj A Dadhania wrote:

quoted

@@ -70,6 +67,17 @@ void cpu_init_fred_exceptions(void)
 	/* Use int $0x80 for 32-bit system calls in FRED mode */
 	setup_clear_cpu_cap(X86_FEATURE_SYSFAST32);
 	setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
+
+	/*
+	 * For secondary processors, FRED bit in CR4 gets enabled in cr4_init()
+	 * and FRED MSRs are not configured till the end of this function. For
+	 * SEV-ES and SNP guests, any console write before the FRED MSRs are
+	 * setup will cause a #VC and cannot be handled. Move the pr_info to
+	 * the end of this function.
+	 *
+	 * When FRED is enabled by default, remove this log message
+	 */
+	pr_info("Initialized FRED on CPU%d\n", smp_processor_id());

Did you forget to fix this up?

I didn't forget, I have moved the message to the end of cpu_init_fred_exceptions()
because the original placement triggered #VC exceptions on SEV-ES/SNP guests before
FRED MSRs were configured, causing boot failures.

Also, when the kernel is working properly, it is quiet, so why is this
log message needed?

thanks,

greg k-h