Revision 002e062e13db10973adb8302f231e48b477c7ccf authored by Yonatan Cohen on 16 November 2016, 08:39:15 UTC, committed by Doug Ledford on 17 November 2016, 01:03:44 UTC
To correctly handle a erroneous WR this fix does the following 1. Make sure the bad WQE causes a user completion event. 2. Call rxe_completer to handle the erred WQE. Before the fix, when rxe_requester found a bad WQE, it changed its status to IB_WC_LOC_PROT_ERR and exit with 0 for non RC QPs. If this was the 1st WQE then there would be no ACK to invoke the completer and this bad WQE would be stuck in the QP's send-q. On top of that the requester exiting with 0 caused rxe_do_task to endlessly invoke rxe_requester, resulting in a soft-lockup attached below. In case the WQE was not the 1st and rxe_completer did get a chance to handle the bad WQE, it did not cause a complete event since the WQE's IB_SEND_SIGNALED flag was not set. Setting WQE status to IB_SEND_SIGNALED is subject to IBA spec version 1.2.1, section 10.7.3.1 Signaled Completions. NMI watchdog: BUG: soft lockup - CPU#7 stuck for 22s! [<ffffffffa0590145>] ? rxe_pool_get_index+0x35/0xb0 [rdma_rxe] [<ffffffffa05952ec>] lookup_mem+0x3c/0xc0 [rdma_rxe] [<ffffffffa0595534>] copy_data+0x1c4/0x230 [rdma_rxe] [<ffffffffa058c180>] rxe_requester+0x9d0/0x1100 [rdma_rxe] [<ffffffff8158e98a>] ? kfree_skbmem+0x5a/0x60 [<ffffffffa05962c9>] rxe_do_task+0x89/0xf0 [rdma_rxe] [<ffffffffa05963e2>] rxe_run_task+0x12/0x30 [rdma_rxe] [<ffffffffa059110a>] rxe_post_send+0x41a/0x550 [rdma_rxe] [<ffffffff811ef922>] ? __kmalloc+0x182/0x200 [<ffffffff816ba512>] ? down_read+0x12/0x40 [<ffffffffa054bd32>] ib_uverbs_post_send+0x532/0x540 [ib_uverbs] [<ffffffff815f8722>] ? tcp_sendmsg+0x402/0xb80 [<ffffffffa05453dc>] ib_uverbs_write+0x18c/0x3f0 [ib_uverbs] [<ffffffff81623c2e>] ? inet_recvmsg+0x7e/0xb0 [<ffffffff8158764d>] ? sock_recvmsg+0x3d/0x50 [<ffffffff81215b87>] __vfs_write+0x37/0x140 [<ffffffff81216892>] vfs_write+0xb2/0x1b0 [<ffffffff81217ce5>] SyS_write+0x55/0xc0 [<ffffffff816bc672>] entry_SYSCALL_64_fastpath+0x1a/0xa Fixes: 8700e3e7c485 ("Soft RoCE driver") Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com> Reviewed-by: Moni Shoua <monis@mellanox.com> Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Doug Ledford <dledford@redhat.com>
1 parent 1454ca3
plist.c
/*
* lib/plist.c
*
* Descending-priority-sorted double-linked list
*
* (C) 2002-2003 Intel Corp
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>.
*
* 2001-2005 (c) MontaVista Software, Inc.
* Daniel Walker <dwalker@mvista.com>
*
* (C) 2005 Thomas Gleixner <tglx@linutronix.de>
*
* Simplifications of the original code by
* Oleg Nesterov <oleg@tv-sign.ru>
*
* Licensed under the FSF's GNU Public License v2 or later.
*
* Based on simple lists (include/linux/list.h).
*
* This file contains the add / del functions which are considered to
* be too large to inline. See include/linux/plist.h for further
* information.
*/
#include <linux/bug.h>
#include <linux/plist.h>
#ifdef CONFIG_DEBUG_PI_LIST
static struct plist_head test_head;
static void plist_check_prev_next(struct list_head *t, struct list_head *p,
struct list_head *n)
{
WARN(n->prev != p || p->next != n,
"top: %p, n: %p, p: %p\n"
"prev: %p, n: %p, p: %p\n"
"next: %p, n: %p, p: %p\n",
t, t->next, t->prev,
p, p->next, p->prev,
n, n->next, n->prev);
}
static void plist_check_list(struct list_head *top)
{
struct list_head *prev = top, *next = top->next;
plist_check_prev_next(top, prev, next);
while (next != top) {
prev = next;
next = prev->next;
plist_check_prev_next(top, prev, next);
}
}
static void plist_check_head(struct plist_head *head)
{
if (!plist_head_empty(head))
plist_check_list(&plist_first(head)->prio_list);
plist_check_list(&head->node_list);
}
#else
# define plist_check_head(h) do { } while (0)
#endif
/**
* plist_add - add @node to @head
*
* @node: &struct plist_node pointer
* @head: &struct plist_head pointer
*/
void plist_add(struct plist_node *node, struct plist_head *head)
{
struct plist_node *first, *iter, *prev = NULL;
struct list_head *node_next = &head->node_list;
plist_check_head(head);
WARN_ON(!plist_node_empty(node));
WARN_ON(!list_empty(&node->prio_list));
if (plist_head_empty(head))
goto ins_node;
first = iter = plist_first(head);
do {
if (node->prio < iter->prio) {
node_next = &iter->node_list;
break;
}
prev = iter;
iter = list_entry(iter->prio_list.next,
struct plist_node, prio_list);
} while (iter != first);
if (!prev || prev->prio != node->prio)
list_add_tail(&node->prio_list, &iter->prio_list);
ins_node:
list_add_tail(&node->node_list, node_next);
plist_check_head(head);
}
/**
* plist_del - Remove a @node from plist.
*
* @node: &struct plist_node pointer - entry to be removed
* @head: &struct plist_head pointer - list head
*/
void plist_del(struct plist_node *node, struct plist_head *head)
{
plist_check_head(head);
if (!list_empty(&node->prio_list)) {
if (node->node_list.next != &head->node_list) {
struct plist_node *next;
next = list_entry(node->node_list.next,
struct plist_node, node_list);
/* add the next plist_node into prio_list */
if (list_empty(&next->prio_list))
list_add(&next->prio_list, &node->prio_list);
}
list_del_init(&node->prio_list);
}
list_del_init(&node->node_list);
plist_check_head(head);
}
/**
* plist_requeue - Requeue @node at end of same-prio entries.
*
* This is essentially an optimized plist_del() followed by
* plist_add(). It moves an entry already in the plist to
* after any other same-priority entries.
*
* @node: &struct plist_node pointer - entry to be moved
* @head: &struct plist_head pointer - list head
*/
void plist_requeue(struct plist_node *node, struct plist_head *head)
{
struct plist_node *iter;
struct list_head *node_next = &head->node_list;
plist_check_head(head);
BUG_ON(plist_head_empty(head));
BUG_ON(plist_node_empty(node));
if (node == plist_last(head))
return;
iter = plist_next(node);
if (node->prio != iter->prio)
return;
plist_del(node, head);
plist_for_each_continue(iter, head) {
if (node->prio != iter->prio) {
node_next = &iter->node_list;
break;
}
}
list_add_tail(&node->node_list, node_next);
plist_check_head(head);
}
#ifdef CONFIG_DEBUG_PI_LIST
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/init.h>
static struct plist_node __initdata test_node[241];
static void __init plist_test_check(int nr_expect)
{
struct plist_node *first, *prio_pos, *node_pos;
if (plist_head_empty(&test_head)) {
BUG_ON(nr_expect != 0);
return;
}
prio_pos = first = plist_first(&test_head);
plist_for_each(node_pos, &test_head) {
if (nr_expect-- < 0)
break;
if (node_pos == first)
continue;
if (node_pos->prio == prio_pos->prio) {
BUG_ON(!list_empty(&node_pos->prio_list));
continue;
}
BUG_ON(prio_pos->prio > node_pos->prio);
BUG_ON(prio_pos->prio_list.next != &node_pos->prio_list);
prio_pos = node_pos;
}
BUG_ON(nr_expect != 0);
BUG_ON(prio_pos->prio_list.next != &first->prio_list);
}
static void __init plist_test_requeue(struct plist_node *node)
{
plist_requeue(node, &test_head);
if (node != plist_last(&test_head))
BUG_ON(node->prio == plist_next(node)->prio);
}
static int __init plist_test(void)
{
int nr_expect = 0, i, loop;
unsigned int r = local_clock();
printk(KERN_DEBUG "start plist test\n");
plist_head_init(&test_head);
for (i = 0; i < ARRAY_SIZE(test_node); i++)
plist_node_init(test_node + i, 0);
for (loop = 0; loop < 1000; loop++) {
r = r * 193939 % 47629;
i = r % ARRAY_SIZE(test_node);
if (plist_node_empty(test_node + i)) {
r = r * 193939 % 47629;
test_node[i].prio = r % 99;
plist_add(test_node + i, &test_head);
nr_expect++;
} else {
plist_del(test_node + i, &test_head);
nr_expect--;
}
plist_test_check(nr_expect);
if (!plist_node_empty(test_node + i)) {
plist_test_requeue(test_node + i);
plist_test_check(nr_expect);
}
}
for (i = 0; i < ARRAY_SIZE(test_node); i++) {
if (plist_node_empty(test_node + i))
continue;
plist_del(test_node + i, &test_head);
nr_expect--;
plist_test_check(nr_expect);
}
printk(KERN_DEBUG "end plist test\n");
return 0;
}
module_init(plist_test);
#endif
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