On Saturday 15 May 2010, Nigel Cunningham wrote: > Hi. > > On 15/05/10 12:37, Alan Stern wrote: > > On Fri, 14 May 2010, Nigel Cunningham wrote: > > > >> Hi. > > > >>> Subject: [PATCH] fs: prevent hang on suspend/resume when MMC/SD card present > >>> > >>> Devices can come and go bus during suspend or resume, when the > >>> writeback thread is frozen, resulting in a hang. Prevent the hang > >>> by thawing the writeback thread in del_gendisk(). > > > >> Why not just make it unfreezeable to start with? > > > > If the writeback thread were unfreezable, it might wake up and try to > > write dirty pages back to disks after they were already suspended. > > That would not lead to good consequences... > > If it syncs data as it should when we freeze processes, there won't be > any problem. Perhaps this is just an argument against making syncing > optional? No, there is a problem. The writeback threads were made freezable after some people had reported hangs during suspend that had been tracked down to that issue. IIRC. Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
