A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-28 18:51:56 -04:00
Code Issues Projects Releases Packages Wiki Activity

ipc,shm: move BUG_ON check into shm_lock

Browse source 
Upon every shm_lock call, we BUG_ON if an error was returned, indicating
racing either in idr or in shm_destroy.  Move this logic into the locking.

[[email protected]: simplify code]
Signed-off-by: Davidlohr Bueso <[email protected]>
Cc: Manfred Spraul <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Davidlohr Bueso 2015-06-30 14:58:36 -07:00 • committed by Linus Torvalds
commit c5c8975b2e
1 changed files with 5 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

10
ipc/shm.c
View file

@ -155,8 +155,11 @@ static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
{
struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
if (IS_ERR(ipcp))
return (struct shmid_kernel *)ipcp;
/*
* We raced in the idr lookup or with shm_destroy(). Either way, the
* ID is busted.
*/
BUG_ON(IS_ERR(ipcp));
return container_of(ipcp, struct shmid_kernel, shm_perm);
}
@ -191,7 +194,6 @@ static void shm_open(struct vm_area_struct *vma)
struct shmid_kernel *shp;
shp = shm_lock(sfd->ns, sfd->id);
BUG_ON(IS_ERR(shp));
shp->shm_atim = get_seconds();
shp->shm_lprid = task_tgid_vnr(current);
shp->shm_nattch++;
@ -258,7 +260,6 @@ static void shm_close(struct vm_area_struct *vma)
down_write(&shm_ids(ns).rwsem);
/* remove from the list of attaches of the shm segment */
shp = shm_lock(ns, sfd->id);
BUG_ON(IS_ERR(shp));
shp->shm_lprid = task_tgid_vnr(current);
shp->shm_dtim = get_seconds();
shp->shm_nattch--;
@ -1191,7 +1192,6 @@ out_fput:
out_nattch:
down_write(&shm_ids(ns).rwsem);
shp = shm_lock(ns, shmid);
BUG_ON(IS_ERR(shp));
shp->shm_nattch--;
if (shm_may_destroy(ns, shp))
shm_destroy(ns, shp);