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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-31 20:53:34 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-31 20:53:34 +0300 |
commit | 8164c5719b864da3bcfee97ad8af8cfd7ee5ad8c (patch) | |
tree | 2259ef4e7a709c9edc2417adacf3da97c6075a47 /drivers/xen/xenbus | |
parent | 27a03b1a71b9adfa7f4ef3f61452fb3bc5b195b1 (diff) | |
parent | d10e0cc113c9e1b64b5c6e3db37b5c839794f3df (diff) | |
download | linux-8164c5719b864da3bcfee97ad8af8cfd7ee5ad8c.tar.xz |
Merge tag 'for-linus-5.2b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"One minor cleanup patch and a fix for handling of live migration when
running as Xen guest"
* tag 'for-linus-5.2b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xenbus: Avoid deadlock during suspend due to open transactions
xen/pvcalls: Remove set but not used variable
Diffstat (limited to 'drivers/xen/xenbus')
-rw-r--r-- | drivers/xen/xenbus/xenbus.h | 3 | ||||
-rw-r--r-- | drivers/xen/xenbus/xenbus_dev_frontend.c | 18 | ||||
-rw-r--r-- | drivers/xen/xenbus/xenbus_xs.c | 7 |
3 files changed, 26 insertions, 2 deletions
diff --git a/drivers/xen/xenbus/xenbus.h b/drivers/xen/xenbus/xenbus.h index 092981171df1..d75a2385b37c 100644 --- a/drivers/xen/xenbus/xenbus.h +++ b/drivers/xen/xenbus/xenbus.h @@ -83,6 +83,7 @@ struct xb_req_data { int num_vecs; int err; enum xb_req_state state; + bool user_req; void (*cb)(struct xb_req_data *); void *par; }; @@ -133,4 +134,6 @@ void xenbus_ring_ops_init(void); int xenbus_dev_request_and_reply(struct xsd_sockmsg *msg, void *par); void xenbus_dev_queue_reply(struct xb_req_data *req); +extern unsigned int xb_dev_generation_id; + #endif diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c index faf452d0edf0..08adc590f631 100644 --- a/drivers/xen/xenbus/xenbus_dev_frontend.c +++ b/drivers/xen/xenbus/xenbus_dev_frontend.c @@ -62,6 +62,8 @@ #include "xenbus.h" +unsigned int xb_dev_generation_id; + /* * An element of a list of outstanding transactions, for which we're * still waiting a reply. @@ -69,6 +71,7 @@ struct xenbus_transaction_holder { struct list_head list; struct xenbus_transaction handle; + unsigned int generation_id; }; /* @@ -441,6 +444,7 @@ static int xenbus_write_transaction(unsigned msg_type, rc = -ENOMEM; goto out; } + trans->generation_id = xb_dev_generation_id; list_add(&trans->list, &u->transactions); } else if (msg->hdr.tx_id != 0 && !xenbus_get_transaction(u, msg->hdr.tx_id)) @@ -449,6 +453,20 @@ static int xenbus_write_transaction(unsigned msg_type, !(msg->hdr.len == 2 && (!strcmp(msg->body, "T") || !strcmp(msg->body, "F")))) return xenbus_command_reply(u, XS_ERROR, "EINVAL"); + else if (msg_type == XS_TRANSACTION_END) { + trans = xenbus_get_transaction(u, msg->hdr.tx_id); + if (trans && trans->generation_id != xb_dev_generation_id) { + list_del(&trans->list); + kfree(trans); + if (!strcmp(msg->body, "T")) + return xenbus_command_reply(u, XS_ERROR, + "EAGAIN"); + else + return xenbus_command_reply(u, + XS_TRANSACTION_END, + "OK"); + } + } rc = xenbus_dev_request_and_reply(&msg->hdr, u); if (rc && trans) { diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index 49a3874ae6bb..ddc18da61834 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -105,6 +105,7 @@ static void xs_suspend_enter(void) static void xs_suspend_exit(void) { + xb_dev_generation_id++; spin_lock(&xs_state_lock); xs_suspend_active--; spin_unlock(&xs_state_lock); @@ -125,7 +126,7 @@ static uint32_t xs_request_enter(struct xb_req_data *req) spin_lock(&xs_state_lock); } - if (req->type == XS_TRANSACTION_START) + if (req->type == XS_TRANSACTION_START && !req->user_req) xs_state_users++; xs_state_users++; rq_id = xs_request_id++; @@ -140,7 +141,7 @@ void xs_request_exit(struct xb_req_data *req) spin_lock(&xs_state_lock); xs_state_users--; if ((req->type == XS_TRANSACTION_START && req->msg.type == XS_ERROR) || - (req->type == XS_TRANSACTION_END && + (req->type == XS_TRANSACTION_END && !req->user_req && !WARN_ON_ONCE(req->msg.type == XS_ERROR && !strcmp(req->body, "ENOENT")))) xs_state_users--; @@ -286,6 +287,7 @@ int xenbus_dev_request_and_reply(struct xsd_sockmsg *msg, void *par) req->num_vecs = 1; req->cb = xenbus_dev_queue_reply; req->par = par; + req->user_req = true; xs_send(req, msg); @@ -313,6 +315,7 @@ static void *xs_talkv(struct xenbus_transaction t, req->vec = iovec; req->num_vecs = num_vecs; req->cb = xs_wake_up; + req->user_req = false; msg.req_id = 0; msg.tx_id = t.id; |