On Fri, Apr 26, 2019 at 12:41 PM David Gibson <da...@gibson.dropbear.id.au> wrote: > > On Fri, Apr 26, 2019 at 11:05:17AM +1000, David Gibson wrote: > > On Thu, Apr 25, 2019 at 08:19:58AM +0200, Christoph Hellwig wrote: > > > Just curious: What exact trees do you see this with? This area > > > changed a lot with the multipage bvec support, and subsequent fixes. > > > > So, I tried it with 576ed913 itself and with 576ed913^ to verify that > > it didn't happen there. The problem also occurred with Linus' tree as > > of when I started bisecting, which appears to have been 444fe991. > > Actually, come to that, here's the whole bisect log in case it's > > helpful: > > > > # git bisect log > > git bisect start > > # good: [bebc6082da0a9f5d47a1ea2edc099bf671058bd4] Linux 4.14 > > git bisect good bebc6082da0a9f5d47a1ea2edc099bf671058bd4 > > # bad: [444fe991353987c1c9bc5ab1f903d01f1b4ad415] Merge tag > > 'riscv-for-linus-5.1-rc6' of > > git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux > > git bisect bad 444fe991353987c1c9bc5ab1f903d01f1b4ad415 > > # good: [399c4129eba6145924ab90363352b7bdcd554751] Merge tag > > 'pxa-for-4.19-dma_slave_map' of https://github.com/rjarzmik/linux > > git bisect good 399c4129eba6145924ab90363352b7bdcd554751 > > # bad: [73b6f96cbc0162787bcbdac5f538167084c8d605] Merge branch > > 'drm-fixes-4.20' of git://people.freedesktop.org/~agd5f/linux into drm-fixes > > git bisect bad 73b6f96cbc0162787bcbdac5f538167084c8d605 > > # good: [85a585918fb4122ad26b6febaec5c3c90bf2535c] Merge tag > > 'loadpin-security-next' of > > https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into next-loadpin > > git bisect good 85a585918fb4122ad26b6febaec5c3c90bf2535c > > # bad: [3acbd2de6bc3af215c6ed7732dfc097d1e238503] Merge tag > > 'sound-4.20-rc1' of > > git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound > > git bisect bad 3acbd2de6bc3af215c6ed7732dfc097d1e238503 > > # good: [8f18da47211554f1ef674fef627c05f23b75a8e0] Merge branch 'master' of > > git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next > > git bisect good 8f18da47211554f1ef674fef627c05f23b75a8e0 > > # bad: [0d1b82cd8ac2e8856ae9045c97782ac1c359929c] Merge branch > > 'ras-core-for-linus' of > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip > > git bisect bad 0d1b82cd8ac2e8856ae9045c97782ac1c359929c > > # bad: [1650ac53066577a5e83fe3e9d992c9311597ff8c] Merge tag 'mmc-v4.20' of > > git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc > > git bisect bad 1650ac53066577a5e83fe3e9d992c9311597ff8c > > # bad: [6ab9e09238fdfd742fe23b81e2d385a1cab49d9b] Merge tag > > 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block > > git bisect bad 6ab9e09238fdfd742fe23b81e2d385a1cab49d9b > > # good: [528985117126f11beea339cf39120ee99da04cd2] Merge tag > > 'arm64-upstream' of > > git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux > > git bisect good 528985117126f11beea339cf39120ee99da04cd2 > > # bad: [2cf99bbd106f89fc72f778e8ad9d5538f1ef939b] lightnvm: pblk: add > > helpers for chunk addresses > > git bisect bad 2cf99bbd106f89fc72f778e8ad9d5538f1ef939b > > # bad: [33b14f67a4e1eabd219fd6543da8f15ed86b641c] nvme: register ns_id > > attributes as default sysfs groups > > git bisect bad 33b14f67a4e1eabd219fd6543da8f15ed86b641c > > # bad: [27ca1d4ed04ea29dc77b47190a3cc82697023e76] block: move > > req_gap_back_merge to blk.h > > git bisect bad 27ca1d4ed04ea29dc77b47190a3cc82697023e76 > > # bad: [07b05bcc3213ac9f8c28c9d835b4bf3d5798cc60] blkcg: convert > > blkg_lookup_create to find closest blkg > > git bisect bad 07b05bcc3213ac9f8c28c9d835b4bf3d5798cc60 > > # good: [cbeb869a3d1110450186b738199963c5e68c2a71] block, bfq: correctly > > charge and reset entity service in all cases > > git bisect good cbeb869a3d1110450186b738199963c5e68c2a71 > > # bad: [576ed9135489c723fb39b97c4e2c73428d06dd78] block: use bio_add_page > > in bio_iov_iter_get_pages > > git bisect bad 576ed9135489c723fb39b97c4e2c73428d06dd78 > > # good: [c8765de0adfcaaf4ffb2d951e07444f00ffa9453] blok, bfq: do not plug > > I/O if all queues are weight-raised > > git bisect good c8765de0adfcaaf4ffb2d951e07444f00ffa9453 > > # first bad commit: [576ed9135489c723fb39b97c4e2c73428d06dd78] block: use > > bio_add_page in bio_iov_iter_get_pages > > > > The problem also occurred with the RHEL8 downstream kernel tree. > > That's based on 4.18, but has 576ed913 backported. > > > > > So I'd be really curious if it can be reproduced with Jens' latest > > > block for-5.2 tree (which should be in latest linux-next). > > > > I'll see if I can try that when I next get access to the machine. > > Ok, I've now had a chance to test the next-20190423 tree. > > I can still reproduce the problem: in fact it is substantially worse, > and somewhat more consistent. > > Previously I usually lost 2-3 hugepages per run, though I'd > occasionally seen other values between 0 and 8. With the next tree, I > lost 46 hugepages on most runs, though I also saw 45 and 48 > occasionally.
Please try to apply the following three patches, and I guess you may see same behavior as linus tree(v5.1-rc, or v4.18). And the last one has been applied to for-5.2/block which should be the latest next. https://lore.kernel.org/linux-block/20190426104521.30602-2-ming....@redhat.com/T/#u https://lore.kernel.org/linux-block/20190426104521.30602-3-ming....@redhat.com/T/#u https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?h=for-5.2/block&id=0257c0ed5ea3de3e32cb322852c4c40bc09d1b97 Thanks, Ming Lei
