On Thu, Aug 29, 2019 at 10:13:20AM -0500, Tyler Hicks wrote: > Hello, Sasha! > > On 2019-08-29 06:49:51, Sasha Levin wrote: > > From: Tyler Hicks <tyhicks@xxxxxxxxxxxxx> > > > > [ Upstream commit 60d4885710836595192c42d3e04b27551d30ec91 ] > > > > Restore the behavior of locking mmap_sem for reading in > > binder_alloc_free_page(), as was first done in commit 3013bf62b67a > > ("binder: reduce mmap_sem write-side lock"). That change was > > inadvertently reverted by commit 5cec2d2e5839 ("binder: fix race between > > munmap() and direct reclaim"). > > > > In addition, change the name of the label for the error path to > > accurately reflect that we're taking the lock for reading. > > > > Backporting note: This fix is only needed when *both* of the commits > > mentioned above are applied. That's an unlikely situation since they > > both landed during the development of v5.1 but only one of them is > > targeted for stable. > > This patch isn't meant to be applied to 4.19 since commit 3013bf62b67a > ("binder: reduce mmap_sem write-side lock") was never brought back to > 4.19. > > Tyler > > > > > Fixes: 5cec2d2e5839 ("binder: fix race between munmap() and direct reclaim") But this commit is in 4.19.49 thanks, greg k-h