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charset=UTF-8 Content-Transfer-Encoding: 8bit X-bounce-key: webpack.hosteurope.de;regressions@leemhuis.info;1688547130;42f81d2b; X-HE-SMSGID: 1qGyF1-0002O0-Fp X-Rspam-User: X-Stat-Signature: xqsc3ttmb7ftpw89ogaun7xyubhyhzqq X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 55F4A140015 X-HE-Tag: 1688547130-854107 X-HE-Meta: U2FsdGVkX1+3KDckubBK+z9C4aCddKnrw5nXEQRrCPyN4RrLZkT9yWUJyLj5jJsm4+bJAeV6GlPjvaBC4Ev0+vlWr3R/XutS7Ljv5OSJea0LWqBuF94WLpgb34mC7dITUke9YM3hOD80TQe9LPL+SboExM4sFSGL4k8bSnjUcFqAHYQ8LtfBrSGRaLYGeOl6WbOGWftxlQzUVqKpR9Hn0VzOtB7U/6tYoHypSBFpQ9Z2TPQ1sQSi182CVZz3swwrohf86DDjgTiS3s6g6qTvAi5HKcgNYB/x3SG51FL9fr/z/5mn9zIP6nMn5v0ZGed1TqcVEKEY+lS1CmAzq+qIM5kfK/UHEZ6vR8mrhY7gmkLL0d7/oYQhfFBrTze9Dnq0xo5DR4d+9ArMA3Bk1opsT8qCDunQCo1GIgwWXxdKyCnVo0z2f49sSOrQzS9tzgLQxIYDcirtjnCy8VYFIyZW8PjxkymRUHV+HpkOC3bUac6RpKashmKBo41mY42NooAEUF8gG6T4RInA8Nwa6KS720qNfeV5JPVcVZAiMXtEkQ5eSje7xox+4Wcg21J2zbBPAwk8I2etOK89d4g7Q6cmWikulMq83mCncqGpn77UI71vvhO6/qz8LlcT64rQvi65ht8Cd8bHI2ZmG+CUhdeJYD01HQWfMf4GMz0USrKA6DZBve0tg78sslSBXVWdIZbrG/46V4f+Y3Xe6M1htOToHX6wjZNWD0kajBetR3t27j42qXLLI+8b0oY0sW7KW/6vDp2+iXMBjV/kvRhkSeoF5IeONFeE1PkrfkBGVAhgvNaIdgncRh8WsxkAeQZ8I5rHmU9+Fu5dz5HQ4De82jyFeLXg4cjgaQKBqhnjXaO67FdxO3JbVHLFLEJN4Vx5B5GmJ8ZfNRhYYVE6N73wGA6jo0xMn/j9NgQbI2IGbV+R4diKvVGHf4GvZNvWp1EnKi2bZ65DKd6o2TPqxut3h9z c1NDi3IZ sGJleD3FW01MxelcQk6d2si99o/YX+CaWH7wv/lgByjCXSo/+AQ9x+j6A4nmGEkfD/2u95hV3pMiWGi5ebwqsZUe3QIg3xsapGAIr9ur5w4FJHlf4SduibeMuWcKUrIAacchglNTg4A5PQHj/AjuNoaVpghvbke4V+I3/yHG0AGt1GgdEPBJkl8buR5s3bRYnuyN6+5F2l1RbU7LL10diuoN+IbzfH7O13Ra8GYiDNM9FL2IvP1nQk0z71W4e4NQ05lKclEKnUqoWM4gC0Fs8E6Zkil4pUIj25V5NcKGbjNQvmn7Orrj6x8u8Z0z0kPTMBpZh+j8VBCndvdXxqvtgdsOJArrsuQAyo70SurTywxNT/ywrWned3mYRYev2ncvhB8FLbktXnZg2mEG99vXCNHtB21EDQZ37ldUnC3TDPf0gmGHFd7rARam09A0W/kQj3FJ4/mE8TN4sxluJBz71u4cQN7SBssOZ+HmwtSj6FWC0sfvGJnubkmza9Kmk1oAbhqvw6U/SgvWLFrqSWB6uBEwlE0ItHFaPkY+rppQ+90Ax54LGiW7R4mpoAw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 05.07.23 09:08, Greg KH wrote: > On Tue, Jul 04, 2023 at 01:22:54PM -0700, Suren Baghdasaryan wrote: >> On Tue, Jul 4, 2023 at 9:18 AM Andrew Morton wrote: >>> On Tue, 4 Jul 2023 09:00:19 +0100 Greg KH wrote: >>>>>>>> Thanks! I'll investigate this later today. After discussing with >>>>>>>> Andrew, we would like to disable CONFIG_PER_VMA_LOCK by default until >>>>>>>> the issue is fixed. I'll post a patch shortly. >>>>>>> >>>>>>> Posted at: https://lore.kernel.org/all/20230703182150.2193578-1-surenb@google.com/ >>>>>> >>>>>> As that change fixes something in 6.4, why not cc: stable on it as well? >>>>> >>>>> Sorry, I thought since per-VMA locks were introduced in 6.4 and this >>>>> patch is fixing 6.4 I didn't need to send it to stable for older >>>>> versions. Did I miss something? >>>> >>>> 6.4.y is a stable kernel tree right now, so yes, it needs to be included >>>> there :) >>> >>> I'm in wait-a-few-days-mode on this. To see if we have a backportable >>> fix rather than disabling the feature in -stable. Andrew, how long will you remain in "wait-a-few-days-mode"? Given what Greg said below and that we already had three reports I know of I'd prefer if we could fix this rather sooner than later in mainline -- especially as Arch Linux and openSUSE Tumbleweed likely have switched to 6.4.y already or will do so soon. >> Ok, I think we have a fix posted at [2] and it's cleanly applies to >> 6.4.y stable branch as well. However fork() performance might slightly >> regress, therefore disabling per-VMA locks by default for now seems to >> be preferable even with this fix (see discussion at >> https://lore.kernel.org/all/54cd9ffb-8f4b-003f-c2d6-3b6b0d2cb7d9@google.com/). >> IOW, both [1] and [2] should be applied to 6.4.y stable. Both apply >> cleanly and I CC'ed stable on [2]. Greg, should I send [1] separately >> to stable@vger? > > We can't do anything for stable until it lands in Linus's tree, so if > you didn't happen to have the stable@ tag in the patch, just email us > the git SHA1 and I can pick it up that way. > > thanks, > > greg k-h Ciao, Thorsten