kernel: fix 9p issues

[tuomas: rename the patch from 9p-hacks to something slighly more
meaningful]
Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com>

pkgs/os-specific/linux/kernel/p9-fixes.patch

@@ -0,0 +1,85 @@
+diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
+--- a/fs/9p/vfs_inode.c
++++ b/fs/9p/vfs_inode.c
+@@ -483,6 +483,9 @@ static int v9fs_test_inode(struct inode *inode, void *data)
+ 
+ 	if (v9inode->qid.type != st->qid.type)
+ 		return 0;
++
++	if (v9inode->qid.path != st->qid.path)
++		return 0;
+ 	return 1;
+ }
+ 
+diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
+--- a/fs/9p/vfs_inode_dotl.c
++++ b/fs/9p/vfs_inode_dotl.c
+@@ -87,6 +87,9 @@ static int v9fs_test_inode_dotl(struct inode *inode, void *data)
+ 
+ 	if (v9inode->qid.type != st->qid.type)
+ 		return 0;
++
++	if (v9inode->qid.path != st->qid.path)
++		return 0;
+ 	return 1;
+ }
+ 
+diff --git a/net/9p/client.c b/net/9p/client.c
+index 3ce672af1596..f1c8ad373f90 100644
+--- a/net/9p/client.c
++++ b/net/9p/client.c
+@@ -749,8 +749,7 @@ p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
+ 	}
+ again:
+ 	/* Wait for the response */
+-	err = wait_event_interruptible(*req->wq,
+-				       req->status >= REQ_STATUS_RCVD);
++	err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
+ 
+ 	/*
+ 	 * Make sure our req is coherent with regard to updates in other
+diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c
+index f24b25c25106..f3a4efcf1456 100644
+--- a/net/9p/trans_virtio.c
++++ b/net/9p/trans_virtio.c
+@@ -286,8 +286,8 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req)
+ 		if (err == -ENOSPC) {
+ 			chan->ring_bufs_avail = 0;
+ 			spin_unlock_irqrestore(&chan->lock, flags);
+-			err = wait_event_interruptible(*chan->vc_wq,
+-							chan->ring_bufs_avail);
++			err = wait_event_killable(*chan->vc_wq,
++						  chan->ring_bufs_avail);
+ 			if (err  == -ERESTARTSYS)
+ 				return err;
+ 
+@@ -327,7 +327,7 @@ static int p9_get_mapped_pages(struct virtio_chan *chan,
+ 		 * Other zc request to finish here
+ 		 */
+ 		if (atomic_read(&vp_pinned) >= chan->p9_max_pages) {
+-			err = wait_event_interruptible(vp_wq,
++			err = wait_event_killable(vp_wq,
+ 			      (atomic_read(&vp_pinned) < chan->p9_max_pages));
+ 			if (err == -ERESTARTSYS)
+ 				return err;
+@@ -471,8 +471,8 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
+ 		if (err == -ENOSPC) {
+ 			chan->ring_bufs_avail = 0;
+ 			spin_unlock_irqrestore(&chan->lock, flags);
+-			err = wait_event_interruptible(*chan->vc_wq,
+-						       chan->ring_bufs_avail);
++			err = wait_event_killable(*chan->vc_wq,
++						  chan->ring_bufs_avail);
+ 			if (err  == -ERESTARTSYS)
+ 				goto err_out;
+ 
+@@ -489,8 +489,7 @@ p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req,
+ 	virtqueue_kick(chan->vq);
+ 	spin_unlock_irqrestore(&chan->lock, flags);
+ 	p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n");
+-	err = wait_event_interruptible(*req->wq,
+-				       req->status >= REQ_STATUS_RCVD);
++	err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
+ 	/*
+ 	 * Non kernel buffers are pinned, unpin them
+ 	 */

pkgs/os-specific/linux/kernel/patches.nix

@@ -52,6 +52,11 @@ rec {
       patch = ./bridge-stp-helper.patch;
     };
 
+  p9_fixes =
+    { name = "p9-fixes";
+      patch = ./p9-fixes.patch;
+    };
+
   no_xsave =
     { name = "no-xsave";
       patch = ./no-xsave.patch;

pkgs/top-level/all-packages.nix

@@ -11501,6 +11501,7 @@ with pkgs;
   linux_mptcp = callPackage ../os-specific/linux/kernel/linux-mptcp.nix {
     kernelPatches =
       [ kernelPatches.bridge_stp_helper
+        kernelPatches.p9_fixes
         kernelPatches.packet_fix_race_condition_CVE_2016_8655
         kernelPatches.DCCP_double_free_vulnerability_CVE-2017-6074
       ]
@@ -11521,6 +11522,7 @@ with pkgs;
   linux_3_10 = callPackage ../os-specific/linux/kernel/linux-3.10.nix {
     kernelPatches = with kernelPatches;
       [ bridge_stp_helper
+        p9_fixes
         lguest_entry-linkage
         packet_fix_race_condition_CVE_2016_8655
         DCCP_double_free_vulnerability_CVE-2017-6074
@@ -11535,6 +11537,7 @@ with pkgs;
   linux_4_4 = callPackage ../os-specific/linux/kernel/linux-4.4.nix {
     kernelPatches =
       [ kernelPatches.bridge_stp_helper
+        kernelPatches.p9_fixes
         kernelPatches.cpu-cgroup-v2."4.4"
       ]
       ++ lib.optionals ((platform.kernelArch or null) == "mips")
@@ -11547,6 +11550,7 @@ with pkgs;
   linux_4_9 = callPackage ../os-specific/linux/kernel/linux-4.9.nix {
     kernelPatches =
       [ kernelPatches.bridge_stp_helper
+        kernelPatches.p9_fixes
         # See pkgs/os-specific/linux/kernel/cpu-cgroup-v2-patches/README.md
         # when adding a new linux version
         # !!! 4.7 patch doesn't apply, 4.9 patch not up yet, will keep checking
@@ -11563,6 +11567,7 @@ with pkgs;
   linux_4_10 = callPackage ../os-specific/linux/kernel/linux-4.10.nix {
     kernelPatches =
       [ kernelPatches.bridge_stp_helper
+        kernelPatches.p9_fixes
         # See pkgs/os-specific/linux/kernel/cpu-cgroup-v2-patches/README.md
         # when adding a new linux version
         # !!! 4.7 patch doesn't apply, 4.9 patch not up yet, will keep checking
@@ -11579,6 +11584,7 @@ with pkgs;
   linux_testing = callPackage ../os-specific/linux/kernel/linux-testing.nix {
     kernelPatches = [
       kernelPatches.bridge_stp_helper
+      kernelPatches.p9_fixes
       kernelPatches.modinst_arg_list_too_long
     ] ++ lib.optionals ((platform.kernelArch or null) == "mips") [
       kernelPatches.mips_fpureg_emu