Bug#1120542: linux-image-6.12.48+deb13-cloud-amd64: vTPM failed to initialize on Google Compute Engine SEV and TDX Confidentail VMs
Package: src:linux
Version: 6.12.48-1
Severity: important
X-Debbugs-Cc: debian-amd64@lists.debian.org, korakit@google.com
User: debian-amd64@lists.debian.org
Usertags: amd64
Dear Maintainer,
vTPM devices are failing to initialize on Debian 13. This is a regression compared to Debian 12, which is based on older kernel and is not affected.
This causes the attestation process to fail on Confidential VM running Debian 13.
A part of kernel log related to this issue is provided below.
The root cause is an upstream Linux kernel patch (commit# 8e690b817e38) first included in kernel v6.12, which changed the default memory caching mode for SEV-SNP and TDX and caused vTPM initialization to fail.
A fix for this regression has been merged upstream and will be included in v6.18 kernel.
We suggest Debian maintainers to either:
1. Revert the problematic patch (8e690b817e38) in the Debian 13 kernel. or
2. Backport the fix from upstream v6.18 to the Debian 13 kernel.
Korakit Seemakhupt
*** Reporter, please consider answering these questions, where appropriate ***
* What led up to the situation?
* What exactly did you do (or not do) that was effective (or
ineffective)?
* What was the outcome of this action?
* What outcome did you expect instead?
*** End of the template - remove these template lines ***
-- Package-specific info:
** Version:
Linux version 6.12.48+deb13-cloud-amd64 (debian-kernel@lists.debian.org) (x86_64-linux-gnu-gcc-14 (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44) #1 SMP PREEMPT_DYNAMIC Debian 6.12.48-1 (2025-09-20)
** Kernel log:
[ 2.162450] ioremap error for 0xfed40000-0xfed45000, requested 0x2, got 0x0
[ 2.169640] tpm_tis MSFT0101:00: probe with driver tpm_tis failed with error -12
Reply to: