Re: [tip:x86/sev] [x86/sev] 06685975c2: BUG:kernel_failed_in_early-boot_stage,last_printk:Booting_the_kernel(entry_offset:#)

[Borislav Petkov]

On Wed, Jul 10, 2024 at 09:47:36AM +0800, Oliver Sang wrote:
> no. when this bisect done, we tested the branch tip 8434cf006ceae,
> the issue is still persistent.

Ok, I think that should fix it:

From: "Borislav Petkov (AMD)" <bp@xxxxxxxxx>
Date: Wed, 10 Jul 2024 10:16:18 +0200
Subject: [PATCH] x86/coco/sev: Disable KCSAN too

The SEV guest code was moved to x86/coco/ along with the instrumentation
exclusion bits. However, there is a blanket KCSAN disable in
arch/x86/kernel/Makefile due to boot hangs.

Copy that disable to the coco's sev Makefile too.

Fixes:  Fixes: 06685975c209 ("x86/sev: Move SEV compilation units")
Closes: https://lore.kernel.org/oe-lkp/202407091342.46d7dbb-oliver.sang@xxxxxxxxx
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
---
 arch/x86/coco/sev/Makefile | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/coco/sev/Makefile b/arch/x86/coco/sev/Makefile
index 5f72e92b37ff..4e375e7305ac 100644
--- a/arch/x86/coco/sev/Makefile
+++ b/arch/x86/coco/sev/Makefile
@@ -9,3 +9,7 @@ endif
 KASAN_SANITIZE_core.o	:= n
 KMSAN_SANITIZE_core.o	:= n
 KCOV_INSTRUMENT_core.o	:= n
+
+# With some compiler versions the generated code results in boot hangs, caused
+# by several compilation units. To be safe, disable all instrumentation.
+KCSAN_SANITIZE		:= n
-- 
2.43.0

-- 
Regards/Gruss,
    Boris.

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