On Wed, Jul 17, 2024 at 07:48:26AM +0900, Damien Le Moal wrote: > On 7/17/24 01:11, Johan Hovold wrote: > > This reverts commit 7a6bbc2829d4ab592c7e440a6f6f5deb3cd95db4. > > > > The offending commit tried to suppress a double "Starting disk" message > > for some drivers, but instead started spamming the log with bogus > > messages every five seconds: > > > > [ 311.798956] sd 0:0:0:0: [sda] Starting disk > > [ 316.919103] sd 0:0:0:0: [sda] Starting disk > > [ 322.040775] sd 0:0:0:0: [sda] Starting disk > > [ 327.161140] sd 0:0:0:0: [sda] Starting disk > > [ 332.281352] sd 0:0:0:0: [sda] Starting disk > > [ 337.401878] sd 0:0:0:0: [sda] Starting disk > > [ 342.521527] sd 0:0:0:0: [sda] Starting disk > > [ 345.850401] sd 0:0:0:0: [sda] Starting disk > > [ 350.967132] sd 0:0:0:0: [sda] Starting disk > > [ 356.090454] sd 0:0:0:0: [sda] Starting disk > > ... > > > > on machines that do not actually stop the disk on runtime suspend (e.g. > > the Qualcomm sc8280xp CRD with UFS). > > This is odd. If the disk is not being being suspended, why does the platform > even enable runtime PM for it ? This is clearly intended to be supported as sd_do_start_stop() returns false and that prevents sd_start_stop_device() from being called on resume (and similarly on suspend which is why there are no matching stopping disk messages above): [ 32.822189] sd 0:0:0:0: sd_resume_common - runtime = 1, sd_do_start_stop = 0, manage_runtime_start_stop = 0 > Are you sure about this ? Or is it simply that > the runtime pm timer is set to a very low interval ? I haven't tried to determine why runtime pm is used this way, but your patch is clearly broken as it prints a message about starting the disk even when sd_do_start_stop() returns false. > It almost sound like what we need to do here is suppress this message for the > runtime resume case, so something like: No, that would only make things worse as I assume you'd have a stopped disk message without a matching start message for driver that do end up stopping the disk here. > However, I would like to make sure that this platform is not calling > sd_resume_runtime() for nothing every 5s. If that is the case, then there is a > more fundamental problem here and reverting this patch is only hiding that. This is with the Qualcomm UFS driver, but it seems it just relies on the generic ufshcd_pltfrm_init() implementation. Also not sure why anyone would want to see these messages on every runtime suspend (for drivers that end up taking this path), but that's a separate discussion. Johan
