Hi, we had recently reports [1,2] of troubles with runtime writes to various SLUB per-cache sysfs files related to slub_debug or tuning leading to crashes. I have inspected all those writable files and the rather unfortunate result is that most of them are made read-only by this patchset, as fixing the issues doesn't seem viable. Details for each are given in each patch. I expect some resistance, hence the RFC. The runtime toggles were however necessary for the use case described in [3], so the first patch extends the slub_debug boot parameter syntax to achieve the same configuration without runtime toggles. That should hopefully make the changes more feasible. [1] https://lkml.kernel.org/r/1580379523-32272-1-git-send-email-vjitta@xxxxxxxxxxxxxx [2] https://lore.kernel.org/r/CAG48ez31PP--h6_FzVyfJ4H86QYczAFPdxtJHUEEan+7VJETAQ@xxxxxxxxxxxxxx [3] https://lore.kernel.org/r/1383cd32-1ddc-4dac-b5f8-9c42282fa81c@xxxxxxxxxxxxxx Vlastimil Babka (5): mm, slub: extend slub_debug syntax for multiple blocks mm, slub: make some slub_debug related attributes read-only mm, slub: remove runtime allocation order changes mm, slub: make remaining slub_debug related attributes read-only mm, slub: make reclaim_account attribute read-only .../admin-guide/kernel-parameters.txt | 2 +- Documentation/vm/slub.rst | 36 +- mm/slub.c | 315 ++++++++---------- 3 files changed, 163 insertions(+), 190 deletions(-) -- 2.26.2
