From a83354f47331db1214cba4dd8899f2a002295b2f Mon Sep 17 00:00:00 2001 From: Andrew Clayton Date: Wed, 30 Nov 2022 00:13:22 +0000 Subject: [PATCH] Enable the PR_SET_CHILD_SUBREAPER prctl(2) option on Linux. This prctl(2) option can be used to set the "child subreaper" attribute of the calling process. This allows a process to take on the role of 'init', which means the process will inherit descendant processes when their immediate parent terminates. This will be used in an upcoming commit that uses a double fork(2) + unshare(2) to create a new PID namespace. The parent from the second fork will terminate leaving the child process to be inherited by 'init'. Aside from it being better to maintain the parent/child relationships between the various unit processes, without setting this you need to ^C twice to fully quit unit when running in the foreground after the double fork. Reviewed-by: Alejandro Colomar Signed-off-by: Andrew Clayton --- auto/isolation | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/auto/isolation b/auto/isolation index 27f44624..c535e80a 100644 --- a/auto/isolation +++ b/auto/isolation @@ -102,6 +102,19 @@ nxt_feature_test="#include . auto/feature +nxt_feature="prctl(PR_SET_CHILD_SUBREAPER)" +nxt_feature_name=NXT_HAVE_PR_SET_CHILD_SUBREAPER +nxt_feature_run=no +nxt_feature_incs= +nxt_feature_libs= +nxt_feature_test="#include + + int main(void) { + return PR_SET_CHILD_SUBREAPER; + }" +. auto/feature + + nxt_feature="Linux mount()" nxt_feature_name=NXT_HAVE_LINUX_MOUNT nxt_feature_run=no