Re: [SPAM] Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
The gerrit for the master branch is and is still in review https://gerrit.openafs.org/#/c/16700/ As soon as it gets merged into master I'll be doing a pullup for 1.8.x (along with some additional Linux support pullups from master). -- Cheyenne Wills [email protected] On Tue, 10 Mar 2026 08:52:31 -0600 Cheyenne Wills wrote: > The problem was introduced in 6.17 with the Linux commit: > 'new helper: set_default_d_op()' (05fb0e666495c) > > This changed the s_d_op member in the super_block to a private member > and requires the use of the helper function. > > The OpenAFS autoconf test for s_d_op failed which caused a fallback to > an older way of setting the dentry_operations for a dentry, but this > could lead to stale dentries. > > I have a fix that is being reviewed and will be posted to gerrit soon. > > -- > Cheyenne Wills > [email protected] > > > > On Tue, 10 Mar 2026 00:45:00 -0400 > Dave Botsch wrote: > [...] > [...] > [...] > [...] > [...] > > ___ > OpenAFS-info mailing list > [email protected] > https://lists.openafs.org/mailman/listinfo/openafs-info ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
The problem was introduced in 6.17 with the Linux commit: 'new helper: set_default_d_op()' (05fb0e666495c) This changed the s_d_op member in the super_block to a private member and requires the use of the helper function. The OpenAFS autoconf test for s_d_op failed which caused a fallback to an older way of setting the dentry_operations for a dentry, but this could lead to stale dentries. I have a fix that is being reviewed and will be posted to gerrit soon. -- Cheyenne Wills [email protected] On Tue, 10 Mar 2026 00:45:00 -0400 Dave Botsch wrote: > What is the Linux kernel change so that we can check for this change > being back ported into other kernels that have a lesser version > number? Thanks. > > On March 9, 2026 9:47:58 PM Cheyenne Wills > wrote: > > > I believe that I found the problem that can result in stale > > dentries. The fix should be fairly simple. An old configure test > > was masking a change in the Linux kernel. > > > > -- > > Cheyenne Wills > > [email protected] > > > > > > > > On Mon, 9 Mar 2026 14:29:29 +0100 > > Gaja Sophie Peters wrote: > >> TLDR: OpenAFS on Ubuntu with kernel 6.17 is in certain > >> circumstances not updating the Cache on file-deletion or > >> file-creation happening on a different machine, the only fix is: > >> echo 3 >/proc/sys/vm/drop_caches > >> > >> > >> Long version: We discovered a problem with the recent advent of the > >> kernel 6.17 as the newest "hardware enablement kernel" in Ubuntu > >> 24.04. Basically the existence or non-existence of a file is not > >> correctly reflected by the AFS-Cache, when a file is deleted or > >> created on another machine after the file was seen (or not) on the > >> current machine. > >> > >> ### first test: file deletion not propagated > >> #this command on a different machine# echo X >test-afs > >> $ cat test-afs > >> X > >> #this command on the other machine# rm test-afs > >> $ cat test-afs > >> X > >> $ fs flushall > >> $ cat test-afs > >> cat: test-afs: Input/output error > >> #as root# echo 3 >/proc/sys/vm/drop_caches > >> $ cat test-afs > >> cat: test-afs: No such file or directory > >> ### second test: file creation not propagated > >> #this command on a different machine# echo Y >test-afs > >> $ cat test-afs > >> cat: test-afs: No such file or directory > >> $ fs flushall > >> $ cat test-afs > >> cat: test-afs: No such file or directory > >> #as root# echo 3 >/proc/sys/vm/drop_caches > >> $ cat test-afs > >> Y > >> > >> We haven't yet tried to pinpoint at which exact kernel-version that > >> problem got introduced, but the Ubuntu-kernels 6.8 and 6.14 are > >> unaffected, the Ubuntu-kernel 6.17 is affected (kAFS on 6.17 is > >> unaffected). It doesn't make a difference, if the OpenAFS-version > >> is 1.8.14 with the Ubuntu-patches for Kernel 6.17 or if it is > >> OpenAFS 1.8.15 > >> > >> The file server hosting the volume was originally 1.8.13.2-1 from > >> Debian Trixie, but updating to 1.8.15 does not change anything, > >> either. > >> > >> Is this known? Any idea how to deal with it? > >> > >> Greetings, > >> Gaja Peters > >> > >> ___ > >> OpenAFS-info mailing list > >> [email protected] > >> https://lists.openafs.org/mailman/listinfo/openafs-info > > > > ___ > > OpenAFS-info mailing list > > [email protected] > > https://lists.openafs.org/mailman/listinfo/openafs-info > ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
What is the Linux kernel change so that we can check for this change being back ported into other kernels that have a lesser version number? Thanks. On March 9, 2026 9:47:58 PM Cheyenne Wills wrote: I believe that I found the problem that can result in stale dentries. The fix should be fairly simple. An old configure test was masking a change in the Linux kernel. -- Cheyenne Wills [email protected] On Mon, 9 Mar 2026 14:29:29 +0100 Gaja Sophie Peters wrote: TLDR: OpenAFS on Ubuntu with kernel 6.17 is in certain circumstances not updating the Cache on file-deletion or file-creation happening on a different machine, the only fix is: echo 3 >/proc/sys/vm/drop_caches Long version: We discovered a problem with the recent advent of the kernel 6.17 as the newest "hardware enablement kernel" in Ubuntu 24.04. Basically the existence or non-existence of a file is not correctly reflected by the AFS-Cache, when a file is deleted or created on another machine after the file was seen (or not) on the current machine. ### first test: file deletion not propagated #this command on a different machine# echo X >test-afs $ cat test-afs X #this command on the other machine# rm test-afs $ cat test-afs X $ fs flushall $ cat test-afs cat: test-afs: Input/output error #as root# echo 3 >/proc/sys/vm/drop_caches $ cat test-afs cat: test-afs: No such file or directory ### second test: file creation not propagated #this command on a different machine# echo Y >test-afs $ cat test-afs cat: test-afs: No such file or directory $ fs flushall $ cat test-afs cat: test-afs: No such file or directory #as root# echo 3 >/proc/sys/vm/drop_caches $ cat test-afs Y We haven't yet tried to pinpoint at which exact kernel-version that problem got introduced, but the Ubuntu-kernels 6.8 and 6.14 are unaffected, the Ubuntu-kernel 6.17 is affected (kAFS on 6.17 is unaffected). It doesn't make a difference, if the OpenAFS-version is 1.8.14 with the Ubuntu-patches for Kernel 6.17 or if it is OpenAFS 1.8.15 The file server hosting the volume was originally 1.8.13.2-1 from Debian Trixie, but updating to 1.8.15 does not change anything, either. Is this known? Any idea how to deal with it? Greetings, Gaja Peters ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
I believe that I found the problem that can result in stale dentries. The fix should be fairly simple. An old configure test was masking a change in the Linux kernel. -- Cheyenne Wills [email protected] On Mon, 9 Mar 2026 14:29:29 +0100 Gaja Sophie Peters wrote: > TLDR: OpenAFS on Ubuntu with kernel 6.17 is in certain circumstances > not updating the Cache on file-deletion or file-creation happening on > a different machine, the only fix is: echo 3 >/proc/sys/vm/drop_caches > > > Long version: We discovered a problem with the recent advent of the > kernel 6.17 as the newest "hardware enablement kernel" in Ubuntu > 24.04. Basically the existence or non-existence of a file is not > correctly reflected by the AFS-Cache, when a file is deleted or > created on another machine after the file was seen (or not) on the > current machine. > > ### first test: file deletion not propagated > #this command on a different machine# echo X >test-afs > $ cat test-afs > X > #this command on the other machine# rm test-afs > $ cat test-afs > X > $ fs flushall > $ cat test-afs > cat: test-afs: Input/output error > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > cat: test-afs: No such file or directory > ### second test: file creation not propagated > #this command on a different machine# echo Y >test-afs > $ cat test-afs > cat: test-afs: No such file or directory > $ fs flushall > $ cat test-afs > cat: test-afs: No such file or directory > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > Y > > We haven't yet tried to pinpoint at which exact kernel-version that > problem got introduced, but the Ubuntu-kernels 6.8 and 6.14 are > unaffected, the Ubuntu-kernel 6.17 is affected (kAFS on 6.17 is > unaffected). It doesn't make a difference, if the OpenAFS-version is > 1.8.14 with the Ubuntu-patches for Kernel 6.17 or if it is OpenAFS > 1.8.15 > > The file server hosting the volume was originally 1.8.13.2-1 from > Debian Trixie, but updating to 1.8.15 does not change anything, > either. > > Is this known? Any idea how to deal with it? > > Greetings, > Gaja Peters > > ___ > OpenAFS-info mailing list > [email protected] > https://lists.openafs.org/mailman/listinfo/openafs-info ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
Am 09.03.26 um 18:19 schrieb Cheyenne Wills: One quick question, are you using a package for installing the openafs client, or building your own client? Both actually. We tried 1.8.14-1~ppa0~ubuntu24.04.3 from the ppa:openafs/stable (https://launchpad.net/~openafs/+archive/ubuntu/stable) as well as 1.8.15 compiled from the sources from Debian Sid patched with the diff from here: https://www.openafs.org/dl/openafs/1.8.15/openafs-1.8.15.diff and compiled in Ubuntu 24.04. Greetings, Gaja -- +-- | IT-Gruppe, Systemadministration | Universität Hamburg, Fachbereich Mathematik | Bundesstr. 55 (Geomatikum) | Raum 212; Tel. 42838-5175 +-- ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
I was able to reproduce the problem and will continue to investigate further. -- Cheyenne Wills [email protected] On Mon, 9 Mar 2026 14:29:29 +0100 Gaja Sophie Peters wrote: > TLDR: OpenAFS on Ubuntu with kernel 6.17 is in certain circumstances > not updating the Cache on file-deletion or file-creation happening on > a different machine, the only fix is: echo 3 >/proc/sys/vm/drop_caches > > > Long version: We discovered a problem with the recent advent of the > kernel 6.17 as the newest "hardware enablement kernel" in Ubuntu > 24.04. Basically the existence or non-existence of a file is not > correctly reflected by the AFS-Cache, when a file is deleted or > created on another machine after the file was seen (or not) on the > current machine. > > ### first test: file deletion not propagated > #this command on a different machine# echo X >test-afs > $ cat test-afs > X > #this command on the other machine# rm test-afs > $ cat test-afs > X > $ fs flushall > $ cat test-afs > cat: test-afs: Input/output error > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > cat: test-afs: No such file or directory > ### second test: file creation not propagated > #this command on a different machine# echo Y >test-afs > $ cat test-afs > cat: test-afs: No such file or directory > $ fs flushall > $ cat test-afs > cat: test-afs: No such file or directory > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > Y > > We haven't yet tried to pinpoint at which exact kernel-version that > problem got introduced, but the Ubuntu-kernels 6.8 and 6.14 are > unaffected, the Ubuntu-kernel 6.17 is affected (kAFS on 6.17 is > unaffected). It doesn't make a difference, if the OpenAFS-version is > 1.8.14 with the Ubuntu-patches for Kernel 6.17 or if it is OpenAFS > 1.8.15 > > The file server hosting the volume was originally 1.8.13.2-1 from > Debian Trixie, but updating to 1.8.15 does not change anything, > either. > > Is this known? Any idea how to deal with it? > > Greetings, > Gaja Peters > > ___ > OpenAFS-info mailing list > [email protected] > https://lists.openafs.org/mailman/listinfo/openafs-info ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
On 3/9/26 6:19 PM, Cheyenne Wills wrote: One quick question, are you using a package for installing the openafs client, or building your own client? We (I am from the same institution) are using OpenAFS 1.8.14-1~ppa0~ubuntu24.04.3 from ppa:openafs/stable, but we have built our own package for 1.8.15 for comparison (which did not make any difference). Thanks for looking into it. Best, Jan Henrik ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
One quick question, are you using a package for installing the openafs client, or building your own client? Thanks. -- Cheyenne Wills [email protected] On Mon, 9 Mar 2026 14:29:29 +0100 Gaja Sophie Peters wrote: > TLDR: OpenAFS on Ubuntu with kernel 6.17 is in certain circumstances > not updating the Cache on file-deletion or file-creation happening on > a different machine, the only fix is: echo 3 >/proc/sys/vm/drop_caches > > > Long version: We discovered a problem with the recent advent of the > kernel 6.17 as the newest "hardware enablement kernel" in Ubuntu > 24.04. Basically the existence or non-existence of a file is not > correctly reflected by the AFS-Cache, when a file is deleted or > created on another machine after the file was seen (or not) on the > current machine. > > ### first test: file deletion not propagated > #this command on a different machine# echo X >test-afs > $ cat test-afs > X > #this command on the other machine# rm test-afs > $ cat test-afs > X > $ fs flushall > $ cat test-afs > cat: test-afs: Input/output error > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > cat: test-afs: No such file or directory > ### second test: file creation not propagated > #this command on a different machine# echo Y >test-afs > $ cat test-afs > cat: test-afs: No such file or directory > $ fs flushall > $ cat test-afs > cat: test-afs: No such file or directory > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > Y > > We haven't yet tried to pinpoint at which exact kernel-version that > problem got introduced, but the Ubuntu-kernels 6.8 and 6.14 are > unaffected, the Ubuntu-kernel 6.17 is affected (kAFS on 6.17 is > unaffected). It doesn't make a difference, if the OpenAFS-version is > 1.8.14 with the Ubuntu-patches for Kernel 6.17 or if it is OpenAFS > 1.8.15 > > The file server hosting the volume was originally 1.8.13.2-1 from > Debian Trixie, but updating to 1.8.15 does not change anything, > either. > > Is this known? Any idea how to deal with it? > > Greetings, > Gaja Peters > > ___ > OpenAFS-info mailing list > [email protected] > https://lists.openafs.org/mailman/listinfo/openafs-info ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
Re: [OpenAFS] AFS-Cache hickups with Ubuntu and Kernel 6.17
Thanks, I'll look into this. I just ran a quick test (non-Ubuntu and with a Linux 6.18 kernel) and wasn't able to duplicate the problem. I'll need to set up an Ubuntu 24.04 system to see if I can duplicate this. -- Cheyenne Wills [email protected] On Mon, 9 Mar 2026 14:29:29 +0100 Gaja Sophie Peters wrote: > TLDR: OpenAFS on Ubuntu with kernel 6.17 is in certain circumstances > not updating the Cache on file-deletion or file-creation happening on > a different machine, the only fix is: echo 3 >/proc/sys/vm/drop_caches > > > Long version: We discovered a problem with the recent advent of the > kernel 6.17 as the newest "hardware enablement kernel" in Ubuntu > 24.04. Basically the existence or non-existence of a file is not > correctly reflected by the AFS-Cache, when a file is deleted or > created on another machine after the file was seen (or not) on the > current machine. > > ### first test: file deletion not propagated > #this command on a different machine# echo X >test-afs > $ cat test-afs > X > #this command on the other machine# rm test-afs > $ cat test-afs > X > $ fs flushall > $ cat test-afs > cat: test-afs: Input/output error > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > cat: test-afs: No such file or directory > ### second test: file creation not propagated > #this command on a different machine# echo Y >test-afs > $ cat test-afs > cat: test-afs: No such file or directory > $ fs flushall > $ cat test-afs > cat: test-afs: No such file or directory > #as root# echo 3 >/proc/sys/vm/drop_caches > $ cat test-afs > Y > > We haven't yet tried to pinpoint at which exact kernel-version that > problem got introduced, but the Ubuntu-kernels 6.8 and 6.14 are > unaffected, the Ubuntu-kernel 6.17 is affected (kAFS on 6.17 is > unaffected). It doesn't make a difference, if the OpenAFS-version is > 1.8.14 with the Ubuntu-patches for Kernel 6.17 or if it is OpenAFS > 1.8.15 > > The file server hosting the volume was originally 1.8.13.2-1 from > Debian Trixie, but updating to 1.8.15 does not change anything, > either. > > Is this known? Any idea how to deal with it? > > Greetings, > Gaja Peters > > ___ > OpenAFS-info mailing list > [email protected] > https://lists.openafs.org/mailman/listinfo/openafs-info ___ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
