On Fri, Nov 02, 2018 at 12:16:02AM +0000, Dexuan Cui wrote:
Hi all, When debugging a memory leak issue (https://github.com/coreos/bugs/issues/2516) with v4.14.11-coreos, we noticed the same issue may have been fixed recently by Roman in the latest mainline (i.e. Linus's master branch) according to comment #7 of https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.launchpad.net_ubun..., which lists these patches (I'm not sure if the 5-patch list is complete):
010cb21d4ede math64: prevent double calculation of DIV64_U64_ROUND_UP() arguments f77d7a05670d mm: don't miss the last page because of round-off error d18bf0af683e mm: drain memcg stocks on css offlining 71cd51b2e1ca mm: rework memcg kernel stack accounting f3a2fccbce15 mm: slowly shrink slabs with a relatively small number of objects
Obviously at least some of the fixes are also needed in the longterm kernels like v4.14.y, but none of the 5 patches has the "Cc: stable@vger.kernel.org" tag? I'm wondering if these patches will be backported to the longterm kernels. BTW, the patches are not in v4.19, but I suppose they will be in v4.19.1-rc1?
Hello, Dexuan!
A couple of issues has been revealed recently, here are fixes (hashes are from the next tree):
5f4b04528b5f mm: don't reclaim inodes with many attached pages 5a03b371ad6a mm: handle no memcg case in memcg_kmem_charge() properly
These two patches should be added to the serie.
Re stable backporting, I'd really wait for some time. Memory reclaim is a quite complex and fragile area, so even if patches are correct by themselves, they can easily cause a regression by revealing some other issues (as it was with the inode reclaim case).
Thanks!