> On Apr 18, 2018, at 11:17 PM, Alexander Shishkin > <[email protected]> wrote: > > On Tue, Apr 17, 2018 at 11:29:07PM -0700, Song Liu wrote: >> As Miklos reported and suggested: >> >> This pattern repeats two times in trace_uprobe.c and in >> kernel/events/core.c as well: >> >> ret = kern_path(filename, LOOKUP_FOLLOW, &path); >> if (ret) >> goto fail_address_parse; >> >> inode = igrab(d_inode(path.dentry)); >> path_put(&path); >> >> And it's wrong. You can only hold a reference to the inode if you >> have an active ref to the superblock as well (which is normally >> through path.mnt) or holding s_umount. > > Oops. I must have snatched it from the uprobe code without thinking. > >> This way unmounting the containing filesystem while the tracepoint is >> active will give you the "VFS: Busy inodes after unmount..." message >> and a crash when the inode is finally put. >> >> Solution: store path instead of inode. >> >> This patch fixes the issue in kernel/event/core.c. >> >> NOTE: Based on my understanding, perf_addr_filter only supports intel_pt. > > Coresight too, but that's probably even further away from what you have. > >> However, my test system doesn't support address filtering (or I made a >> mistake?). Therefore, I have NOT tested this patch. > > Check /sys/devices/intel_pt/caps/num_address_ranges, if it's non-zero, > it's supported. > >> Could someone please help test it? > > Yes: > > Reviewed-and-tested-by: Alexander Shishkin > <[email protected]> > > The subject line needs a little love to be more like other perf commits, but > other than that, looks good. > > Thanks!
Did this patch ever make into tip/perf/XX trees? If not, what shall I do to move it ahead? Thanks, Song
