]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
tpm, tpm_tis: Fix timeout handling when waiting for TPM status
authorJonathan McDowell <noodles@meta.com>
Wed, 12 Mar 2025 05:31:57 +0000 (07:31 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 25 Apr 2025 08:45:23 +0000 (10:45 +0200)
commit3fcff11317b2714c106e2d0acca6bf91b6b2a45f
tree95cf36b00ca7b75e638b70799a163356deee712d
parent9bd51723ab51580e077c91d494c37e80703b8524
tpm, tpm_tis: Fix timeout handling when waiting for TPM status

commit 7146dffa875cd00e7a7f918e1fce79c7593ac1fa upstream.

The change to only use interrupts to handle supported status changes
introduced an issue when it is necessary to poll for the status. Rather
than checking for the status after sleeping the code now sleeps after
the check. This means a correct, but slower, status change on the part
of the TPM can be missed, resulting in a spurious timeout error,
especially on a more loaded system. Switch back to sleeping *then*
checking. An up front check of the status has been done at the start of
the function, so this does not cause an additional delay when the status
is already what we're looking for.

Cc: stable@vger.kernel.org # v6.4+
Fixes: e87fcf0dc2b4 ("tpm, tpm_tis: Only handle supported interrupts")
Signed-off-by: Jonathan McDowell <noodles@meta.com>
Reviewed-by: Michal Suchánek <msuchanek@suse.de>
Reviewed-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/char/tpm/tpm_tis_core.c