From d56f77e17fefcf6fa36367ae4744f5a092dd099f Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 8 Sep 2022 12:57:23 +0200 Subject: [PATCH] measure: print a helpful message if TPM2 PCR sysfs attributes are missing Prompted by: https://github.com/systemd/systemd/pull/24351#pullrequestreview-1100418585 --- src/boot/measure.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/boot/measure.c b/src/boot/measure.c index 33117fe9396..824a270ff25 100644 --- a/src/boot/measure.c +++ b/src/boot/measure.c @@ -279,6 +279,8 @@ static int measure_pcr(PcrState *pcr_states, size_t n) { return log_oom(); r = read_virtual_file(p, 4096, &s, NULL); + if (r == -ENOENT && access("/sys/class/tpm/tpm0/", F_OK) >= 0) + return log_error_errno(r, "TPM device exists, but cannot open '%s'; either the kernel is too old, or selected PCR bank is not supported: %m", p); if (r < 0) return log_error_errno(r, "Failed to read '%s': %m", p); -- 2.47.3