On Tue, Apr 14, 2020 at 07:04:07PM +0300, Jarkko Sakkinen wrote:
On Tue, Apr 14, 2020 at 10:26:32AM +0200, Hans de Goede wrote:
Hi,
On 4/14/20 9:13 AM, Jarkko Sakkinen wrote:
On Mon, Apr 13, 2020 at 08:11:15PM +0200, Hans de Goede wrote:
Hi,
On 4/13/20 8:07 PM, Jarkko Sakkinen wrote:
On Mon, Apr 13, 2020 at 12:04:25PM +0200, Hans de Goede wrote:
Hi Jarkko,
On 4/12/20 7:04 PM, Jarkko Sakkinen wrote: > Call devm_free_irq() if we have to revert to polling in order not to > unnecessarily reserve the IRQ for the life-cycle of the driver. > > Cc: stable@vger.kernel.org # 4.5.x > Reported-by: Hans de Goede hdegoede@redhat.com > Fixes: e3837e74a06d ("tpm_tis: Refactor the interrupt setup") > Signed-off-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com > --- > drivers/char/tpm/tpm_tis_core.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > index 27c6ca031e23..ae6868e7b696 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -1062,9 +1062,12 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, > if (irq) { > tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED, > irq); > - if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) > + if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) { > dev_err(&chip->dev, FW_BUG > "TPM interrupt not working, polling instead\n"); > + devm_free_irq(chip->dev.parent, priv->irq, > + chip); > + }
My initial plan was actually to do something similar, but if the probe code is actually ever fixed to work as intended again then this will lead to a double free as then the IRQ-test path of tpm_tis_send() will have called disable_interrupts() which already calls devm_free_irq().
You could check for chip->irq != 0 here to avoid that.
Erm in case you haven't figured it out yet this should be priv->irq != 0, sorry.
Yup.
But it all is rather messy, which is why I went with the "#if 0" approach in my patch.
I think it is right way to fix it. It is a bug independent of the issue we are experiencing.
However, what you are suggesting should be done in addition. Do you have a patch in place or do you want me to refine mine?
I do not have a patch ready for this, if you can refine yours that would be great.
Thanks! Just wanted to confirm.
And thank you for working on a (temporary?) fix for this.
As far as I see it, it is orthogonal fix that needs to be backported to stable kernels. This bug predates the issue we're seeing now.
Hey, I came to other thoughts on "how". Would probably make sense to always call disable_interrupts() aka no sense to add two separate code paths. What do you think?
/Jarkko