Re: [Crash-utility] [PATCH] Fix the "kmem -s" option for Linux 5.7 and later kernels

-----Original Message----- > Linux 5.7 and later kernels that contain kernel commit <1ad53d9fa3f6> > ("slub: improve bit diffusion for freelist ptr obfuscation") changed > the calculation formula in the freelist_ptr(), which added a swab() > call to mix bits a little more. When kernel is built with the > "CONFIG_SLAB_FREELIST_HARDENED=y",the "kmem -s" option fails with the > following errors, if there is no such patch. > > crash> kmem -s > CACHE OBJSIZE ALLOCATED TOTAL SLABS SSIZE NAME > 82166d00 144 0 0 0 4k fuse_request > 82166e00 792 0 0 0 16k fuse_inode > 87201e00 528 0 0 0 8k xfs_dqtrx > 87201f00 496 0 0 0 8k xfs_dquot > kmem: xfs_buf: slab: 37202e6e900 invalid freepointer: b844bab900001d70 > kmem: xfs_buf: slab: 3720250fd80 invalid freepointer: b8603f9400001370 > ... Good catch! And the patch diff looks good to me.

But the freelist_ptr() function, which is patched, is called only when the error message is NOT printed. So it seems like the patch does not stop the message, right?