> Please try the attached patch and let me know how it goes. > > It applies on top of the current mainline, but it may be adjusted to > older kernels, so please let me know if you need that.
Thanks. The patch seems to be working. /dev/tpm0 and /dev/tpmrm0 are back and a command like tpm2_get_random 16 succeeds. > I think that these messages have been present in the kernel logs for > quite some time, but previously they were not connected to any > functional issues. You are right that the messages were already present before. I see them in the commit before "tpm_crb: Convert ACPI driver to a platform one". Here is what the logs say now: acpi MSFT0101:00: Adjusting resource [mem 0xfed4000-0xfed40fff] to [mem 0xfed40040-0xfed4103f] tpm_crb_acpi MSFT0101:00: [Firmware Bug]: Bad ACPI memory layout The second message was already there before too. I'm sorry for sending multiple times the same email. I'm still learning. On Wed, Aug 5, 2026 at 6:01 PM Rafael J. Wysocki (Intel) <[email protected]> wrote: > > On Tue, Aug 4, 2026 at 9:08 PM Wysocki, Rafael J > <[email protected]> wrote: > > > > Hi, > > > > On 8/2/2026 2:54 PM, Julien wrote: > > > Hello, > > > > > > Please keep in mind this is my first time reporting a Linux kernel > > > regression. > > > > > > Since commit 48fe2cddc85c ("tpm_crb: Convert ACPI driver to a platform > > > one"), my TPM device is no longer available. Both /dev/tpm0 and > > > /dev/tpmrm0 are missing. > > > > > > Log messages: > > > platform MSFT0101:00: failed to claim resource 1: [mem > > > 0xfed40000-0xfed40fff] > > > acpi MSFT0101:00: platform device creation failed: -16 > > > > > So there's no platform device for the driver to bind to. > > > > I think that these messages have been present in the kernel logs for > > quite some time, but previously they were not connected to any > > functional issues. > > > > > > > I added some debug logging: > > > ACPI resourcet[0] = [mem 0xfed40040-0xfed4103f flags 0x200] > > > ACPI resourcet[1] = [mem 0xfed40000-0xfed40fff flags 0x200] > > > > > > I think the failure happens in kernel/resource.c: __insert_resource() > > > because of the two memory regions overlapping. > > > > > This is quite plausible, but if that's the case, it should be fixable. > > > > Let me figure out something. > > Please try the attached patch and let me know how it goes. > > It applies on top of the current mainline, but it may be adjusted to > older kernels, so please let me know if you need that.
