linux/kernel/exit.c, branch v2.6.20

[PATCH] namespaces: fix task exit disaster

2007-01-30T21:40:36Z

This is based on a patch by Eric W. Biederman, who pointed out that pid namespaces are still fake, and we only have one ever active. So for the time being, we can modify any code which could access tsk->nsproxy->pid_ns during task exit to just use &init_pid_ns instead, and move the exit_task_namespaces call in do_exit() back above exit_notify(), so that an exiting nfs server has a valid tsk->sighand to work with. Long term, pulling pid_ns out of nsproxy might be the cleanest solution. Signed-off-by: Eric W. Biederman [ Eric's patch fixed to take care of free_pid() too ] Signed-off-by: Serge E. Hallyn Signed-off-by: Linus Torvalds

Revert "[PATCH] namespaces: fix exit race by splitting exit"

2007-01-30T21:35:18Z

This reverts commit 7a238fcba0629b6f2edbcd37458bae56fcf36be5 in preparation for a better and simpler fix proposed by Eric Biederman (and fixed up by Serge Hallyn) Acked-by: Serge E. Hallyn Signed-off-by: Linus Torvalds

[PATCH] namespaces: fix exit race by splitting exit

2007-01-30T16:26:44Z

Fix exit race by splitting the nsproxy putting into two pieces. First piece reduces the nsproxy refcount. If we dropped the last reference, then it puts the mnt_ns, and returns the nsproxy as a hint to the caller. Else it returns NULL. The second piece of exiting task namespaces sets tsk->nsproxy to NULL, and drops the references to other namespaces and frees the nsproxy only if an nsproxy was passed in. A little awkward and should probably be reworked, but hopefully it fixes the NFS oops. Signed-off-by: Serge E. Hallyn Cc: Herbert Poetzl Cc: Oleg Nesterov Cc: "Eric W. Biederman" Cc: Cedric Le Goater Cc: Daniel Hokka Zakrisson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] restore ->pdeath_signal behaviour

2006-12-31T22:41:18Z

Commit b2b2cbc4b2a2f389442549399a993a8306420baf introduced a user- visible change: ->pdeath_signal is sent only when the entire thread group exits. While this change is imho good, it may break things. So restore the old behaviour for now. Signed-off-by: Oleg Nesterov To: Albert Cahalan Cc: Eric W. Biederman Cc: Andrew Morton Cc: Linus Torvalds Cc: Ingo Molnar Cc: Qi Yong Cc: Roland McGrath Signed-off-by: Linus Torvalds

[PATCH] Fix reparenting to the same thread group. (take 2)

2006-12-22T17:03:41Z

This patch fixes the case when we reparent to a different thread in the same thread group. This modifies the code so that we do not send signals and do not change the signal to send to SIGCHLD unless we have change the thread group of our parents. It also suppresses sending pdeath_sig in this cas as well since the result of geppid doesn't change. Thanks to Oleg for spotting my bug of only fixing this for non-ptraced tasks. Signed-off-by: Eric W. Biederman Cc: Mike Galbraith Cc: Albert Cahalan Cc: Andrew Morton Cc: Roland McGrath Cc: Ingo Molnar Cc: Coywolf Qi Hunt Acked-by: Oleg Nesterov Signed-off-by: Linus Torvalds

[PATCH] fdtable: Provide free_fdtable() wrapper

2006-12-22T16:55:50Z

Christoph Hellwig has expressed concerns that the recent fdtable changes expose the details of the RCU methodology used to release no-longer-used fdtable structures to the rest of the kernel. The trivial patch below addresses these concerns by introducing the appropriate free_fdtable() calls, which simply wrap the release RCU usage. Since free_fdtable() is a one-liner, it makes sense to promote it to an inline helper. Signed-off-by: Vadim Lobanov Cc: Christoph Hellwig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] fdtable: Remove the free_files field

2006-12-10T17:57:22Z

An fdtable can either be embedded inside a files_struct or standalone (after being expanded). When an fdtable is being discarded after all RCU references to it have expired, we must either free it directly, in the standalone case, or free the files_struct it is contained within, in the embedded case. Currently the free_files field controls this behavior, but we can get rid of it entirely, as all the necessary information is already recorded. We can distinguish embedded and standalone fdtables using max_fds, and if it is embedded we can divine the relevant files_struct using container_of(). Signed-off-by: Vadim Lobanov Cc: Christoph Hellwig Cc: Al Viro Cc: Dipankar Sarma Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] fdtable: Make fdarray and fdsets equal in size

2006-12-10T17:57:22Z

Currently, each fdtable supports three dynamically-sized arrays of data: the fdarray and two fdsets. The code allows the number of fds supported by the fdarray (fdtable->max_fds) to differ from the number of fds supported by each of the fdsets (fdtable->max_fdset). In practice, it is wasteful for these two sizes to differ: whenever we hit a limit on the smaller-capacity structure, we will reallocate the entire fdtable and all the dynamic arrays within it, so any delta in the memory used by the larger-capacity structure will never be touched at all. Rather than hogging this excess, we shouldn't even allocate it in the first place, and keep the capacities of the fdarray and the fdsets equal. This patch removes fdtable->max_fdset. As an added bonus, most of the supporting code becomes simpler. Signed-off-by: Vadim Lobanov Cc: Christoph Hellwig Cc: Al Viro Cc: Dipankar Sarma Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] session_of_pgrp: kill unnecessary do_each_task_pid(PIDTYPE_PGID)

2006-12-08T16:28:52Z

All members of the process group have the same sid and it can't be == 0. NOTE: this code (and a similar one in sys_setpgid) was needed because it was possibe to have ->session == 0. It's not possible any longer since [PATCH] pidhash: don't use zero pids Commit: c7c6464117a02b0d54feb4ebeca4db70fa493678 Signed-off-by: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] add child reaper to pid_namespace

2006-12-08T16:28:52Z

Add a per pid_namespace child-reaper. This is needed so processes are reaped within the same pid space and do not spill over to the parent pid space. Its also needed so containers preserve existing semantic that pid == 1 would reap orphaned children. This is based on Eric Biederman's patch: http://lkml.org/lkml/2006/2/6/285 Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Cedric Le Goater Cc: Kirill Korotaev Cc: Eric W. Biederman Cc: Herbert Poetzl Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds