From: Christian Brauner Date: Fri, 4 Apr 2025 14:06:55 +0000 (+0200) Subject: Merge patch series "pidfd: improve uapi when task isn't found" X-Git-Tag: v6.16-rc1~220^2~7 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1e940fff94374d04b6c34f896ed9fbad3d2fb706;p=thirdparty%2Flinux.git Merge patch series "pidfd: improve uapi when task isn't found" Christian Brauner says: We currently report EINVAL whenever a struct pid has no tasked attached anymore thereby conflating two concepts: (1) The task has already been reaped. (2) The caller requested a pidfd for a thread-group leader but the pid actually references a struct pid that isn't used as a thread-group leader. This is causing issues for non-threaded workloads as in [1] where they expect ESRCH to be reported, not EINVAL. I think that's a very resonable assumption. This patch tries to allow userspace to distinguish between (1) and (2). This is racy of course but that shouldn't matter. * patches from https://lore.kernel.org/r/20250403-work-pidfd-fixes-v1-0-a123b6ed6716@kernel.org: selftest/pidfd: add test for thread-group leader pidfd open for thread pidfd: improve uapi when task isn't found pidfd: remove unneeded NULL check from pidfd_prepare() selftests/pidfd: adapt to recent changes Link: https://lore.kernel.org/r/20250403-work-pidfd-fixes-v1-0-a123b6ed6716@kernel.org Signed-off-by: Christian Brauner --- 1e940fff94374d04b6c34f896ed9fbad3d2fb706