481c2d1462
After activation of interrupts for TPM TIS drivers 0-day reports an interrupt storm on an Inspur NF5180M6 server. Fix this by detecting the storm and falling back to polling: Count the number of unhandled interrupts within a 10 ms time interval. In case that more than 1000 were unhandled deactivate interrupts entirely, deregister the handler and use polling instead. Also print a note to point to the tpm_tis_dmi_table. Since the interrupt deregistration function devm_free_irq() waits for all interrupt handlers to finish, only trigger a worker in the interrupt handler and do the unregistration in the worker to avoid a deadlock. Note: the storm detection logic equals the implementation in note_interrupt() which uses timestamps and counters stored in struct irq_desc. Since this structure is private to the generic interrupt core the TPM TIS core uses its own timestamps and counters. Furthermore the TPM interrupt handler always returns IRQ_HANDLED to prevent the generic interrupt core from processing the interrupt storm. Cc: stable@vger.kernel.org # v6.4+ Fixes: e644b2f498d2 ("tpm, tpm_tis: Enable interrupt test") Reported-by: kernel test robot <yujie.liu@intel.com> Closes: https://lore.kernel.org/oe-lkp/202305041325.ae8b0c43-yujie.liu@intel.com/ Suggested-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.