On 01.02.24 17:40, Elliott, Robert (Servers) wrote: > ATTENTION: This e-mail is from an external sender. Please check attachments and links before opening e.g. with mouseover. > > >> From: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx> >> Sent: Thursday, February 1, 2024 5:37 AM >> Subject: [PATCH] tpm,tpm_tis: Avoid warning splat at shutdown >> >> If interrupts are not activated the work struct 'free_irq_work' is not >> initialized. This results in a warning splat at module shutdown. >> >> Fix this by always initializing the work regardless of whether interrupts >> are activated or not. > > That's using flush_work(), which just waits for one to complete. Is there > any case where multiple work entries could be queued, and cancel_work_sync() > would be necessary? > No. There is only one work struct (namely free_irq_work) and it can only be queued once at a time (note that schedule_work() does not queue the same work again if it is already queued). > tpm_tis_probe_irq() has a loop calling tpm_tis_probe_irq_single() > for 3 to 15. Could each of those could trigger an interrupt storm and > call tpm_tis_revert_interrupts(), which calls schedule_work()? > > The iteration stops as soon as there is an interrupt found that "works" (i.e. as soon as one interrupt fires, see the "irq test" in tpm_tis_send()). If this irq starts a storm it is handled by the implemented irq storm handling and deactivated. No other interrupts are activated afterwards. So no, I do not see that multiple interrupt storms are possible at the same time. Regards, Lino
