The patch below does not apply to the 3.13-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 555b270e25b0279b98083518a85f4b1da144a181 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger <[email protected]> Date: Mon, 20 Jan 2014 03:36:24 +0000 Subject: [PATCH] iscsi-target: Fix connection reset hang with percpu_ida_alloc This patch addresses a bug where connection reset would hang indefinately once percpu_ida_alloc() was starved for tags, due to the fact that it always assumed uninterruptible sleep mode. So now make percpu_ida_alloc() check for signal_pending_state() for making interruptible sleep optional, and convert iscsit_allocate_cmd() to set TASK_INTERRUPTIBLE for GFP_KERNEL, or TASK_RUNNING for GFP_ATOMIC. Reported-by: Linus Torvalds <[email protected]> Cc: Kent Overstreet <[email protected]> Cc: <[email protected]> #3.12+ Signed-off-by: Nicholas Bellinger <[email protected]> diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c index 9b8e1db1257b..5477ecabc00e 100644 --- a/drivers/target/iscsi/iscsi_target_util.c +++ b/drivers/target/iscsi/iscsi_target_util.c @@ -156,7 +156,7 @@ struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask) { struct iscsi_cmd *cmd; struct se_session *se_sess = conn->sess->se_sess; - int size, tag, state = (gfp_mask & __GFP_WAIT) ? TASK_UNINTERRUPTIBLE : + int size, tag, state = (gfp_mask & __GFP_WAIT) ? TASK_INTERRUPTIBLE : TASK_RUNNING; tag = percpu_ida_alloc(&se_sess->sess_tag_pool, state); diff --git a/lib/percpu_ida.c b/lib/percpu_ida.c index 58b671484ac2..7be235f1a70b 100644 --- a/lib/percpu_ida.c +++ b/lib/percpu_ida.c @@ -138,14 +138,14 @@ static inline unsigned alloc_local_tag(struct percpu_ida_cpu *tags) * tag_pool_init()), or otherwise -ENOSPC on allocation failure. * * Safe to be called from interrupt context (assuming it isn't passed - * TASK_UNINTERRUPTIBLE, of course). + * TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, of course). * * @gfp indicates whether or not to wait until a free id is available (it's not * used for internal memory allocations); thus if passed __GFP_WAIT we may sleep * however long it takes until another thread frees an id (same semantics as a * mempool). * - * Will not fail if passed TASK_UNINTERRUPTIBLE. + * Will not fail if passed TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE. */ int percpu_ida_alloc(struct percpu_ida *pool, int state) { @@ -195,6 +195,11 @@ int percpu_ida_alloc(struct percpu_ida *pool, int state) if (tag >= 0 || state == TASK_RUNNING) break; + if (signal_pending_state(state, current)) { + tag = -ERESTARTSYS; + break; + } + schedule(); local_irq_save(flags); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
