The patch below does not apply to the 5.10-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 78d0d2063bab954d19a1696feae4c7706a626d48
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062303-urging-acutely-c0f9@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 78d0d2063bab954d19a1696feae4c7706a626d48 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe(a)kernel.dk>
Date: Mon, 19 Jun 2023 09:41:05 -0600
Subject: [PATCH] io_uring/net: disable partial retries for recvmsg with cmsg
We cannot sanely handle partial retries for recvmsg if we have cmsg
attached. If we don't, then we'd just be overwriting the initial cmsg
header on retries. Alternatively we could increment and handle this
appropriately, but it doesn't seem worth the complication.
Move the MSG_WAITALL check into the non-multishot case while at it,
since MSG_WAITALL is explicitly disabled for multishot anyway.
Link: https://lore.kernel.org/io-uring/0b0d4411-c8fd-4272-770b-e030af6919a0@kerne…
Cc: stable(a)vger.kernel.org # 5.10+
Reported-by: Stefan Metzmacher <metze(a)samba.org>
Reviewed-by: Stefan Metzmacher <metze(a)samba.org>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/io_uring/net.c b/io_uring/net.c
index c0924ab1ea11..2bc2cb2f4d6c 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -789,16 +789,19 @@ retry_multishot:
flags = sr->msg_flags;
if (force_nonblock)
flags |= MSG_DONTWAIT;
- if (flags & MSG_WAITALL)
- min_ret = iov_iter_count(&kmsg->msg.msg_iter);
kmsg->msg.msg_get_inq = 1;
- if (req->flags & REQ_F_APOLL_MULTISHOT)
+ if (req->flags & REQ_F_APOLL_MULTISHOT) {
ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
&mshot_finished);
- else
+ } else {
+ /* disable partial retry for recvmsg with cmsg attached */
+ if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg,
kmsg->uaddr, flags);
+ }
if (ret < min_ret) {
if (ret == -EAGAIN && force_nonblock) {
The patch below does not apply to the 5.15-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 78d0d2063bab954d19a1696feae4c7706a626d48
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062302-supremacy-backboned-b263@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 78d0d2063bab954d19a1696feae4c7706a626d48 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe(a)kernel.dk>
Date: Mon, 19 Jun 2023 09:41:05 -0600
Subject: [PATCH] io_uring/net: disable partial retries for recvmsg with cmsg
We cannot sanely handle partial retries for recvmsg if we have cmsg
attached. If we don't, then we'd just be overwriting the initial cmsg
header on retries. Alternatively we could increment and handle this
appropriately, but it doesn't seem worth the complication.
Move the MSG_WAITALL check into the non-multishot case while at it,
since MSG_WAITALL is explicitly disabled for multishot anyway.
Link: https://lore.kernel.org/io-uring/0b0d4411-c8fd-4272-770b-e030af6919a0@kerne…
Cc: stable(a)vger.kernel.org # 5.10+
Reported-by: Stefan Metzmacher <metze(a)samba.org>
Reviewed-by: Stefan Metzmacher <metze(a)samba.org>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/io_uring/net.c b/io_uring/net.c
index c0924ab1ea11..2bc2cb2f4d6c 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -789,16 +789,19 @@ retry_multishot:
flags = sr->msg_flags;
if (force_nonblock)
flags |= MSG_DONTWAIT;
- if (flags & MSG_WAITALL)
- min_ret = iov_iter_count(&kmsg->msg.msg_iter);
kmsg->msg.msg_get_inq = 1;
- if (req->flags & REQ_F_APOLL_MULTISHOT)
+ if (req->flags & REQ_F_APOLL_MULTISHOT) {
ret = io_recvmsg_multishot(sock, sr, kmsg, flags,
&mshot_finished);
- else
+ } else {
+ /* disable partial retry for recvmsg with cmsg attached */
+ if (flags & MSG_WAITALL && !kmsg->msg.msg_controllen)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg,
kmsg->uaddr, flags);
+ }
if (ret < min_ret) {
if (ret == -EAGAIN && force_nonblock) {
The patch below does not apply to the 5.10-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x b1dc492087db0f2e5a45f1072a743d04618dd6be
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062329-stem-resize-ab95@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b1dc492087db0f2e5a45f1072a743d04618dd6be Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe(a)kernel.dk>
Date: Mon, 19 Jun 2023 09:35:34 -0600
Subject: [PATCH] io_uring/net: clear msg_controllen on partial sendmsg retry
If we have cmsg attached AND we transferred partial data at least, clear
msg_controllen on retry so we don't attempt to send that again.
Cc: stable(a)vger.kernel.org # 5.10+
Fixes: cac9e4418f4c ("io_uring/net: save msghdr->msg_control for retries")
Reported-by: Stefan Metzmacher <metze(a)samba.org>
Reviewed-by: Stefan Metzmacher <metze(a)samba.org>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/io_uring/net.c b/io_uring/net.c
index 51b0f7fbb4f5..c0924ab1ea11 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -326,6 +326,8 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
return io_setup_async_msg(req, kmsg, issue_flags);
if (ret > 0 && io_net_retry(sock, flags)) {
+ kmsg->msg.msg_controllen = 0;
+ kmsg->msg.msg_control = NULL;
sr->done_io += ret;
req->flags |= REQ_F_PARTIAL_IO;
return io_setup_async_msg(req, kmsg, issue_flags);
The patch below does not apply to the 5.15-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x b1dc492087db0f2e5a45f1072a743d04618dd6be
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062328-parka-debtor-1040@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b1dc492087db0f2e5a45f1072a743d04618dd6be Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe(a)kernel.dk>
Date: Mon, 19 Jun 2023 09:35:34 -0600
Subject: [PATCH] io_uring/net: clear msg_controllen on partial sendmsg retry
If we have cmsg attached AND we transferred partial data at least, clear
msg_controllen on retry so we don't attempt to send that again.
Cc: stable(a)vger.kernel.org # 5.10+
Fixes: cac9e4418f4c ("io_uring/net: save msghdr->msg_control for retries")
Reported-by: Stefan Metzmacher <metze(a)samba.org>
Reviewed-by: Stefan Metzmacher <metze(a)samba.org>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/io_uring/net.c b/io_uring/net.c
index 51b0f7fbb4f5..c0924ab1ea11 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -326,6 +326,8 @@ int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
return io_setup_async_msg(req, kmsg, issue_flags);
if (ret > 0 && io_net_retry(sock, flags)) {
+ kmsg->msg.msg_controllen = 0;
+ kmsg->msg.msg_control = NULL;
sr->done_io += ret;
req->flags |= REQ_F_PARTIAL_IO;
return io_setup_async_msg(req, kmsg, issue_flags);
The patch below does not apply to the 4.14-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x 067d6ec7ed5b49380688e06c1e5f883a71bef4fe
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062352-unrivaled-feline-e1a2@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 067d6ec7ed5b49380688e06c1e5f883a71bef4fe Mon Sep 17 00:00:00 2001
From: Dexuan Cui <decui(a)microsoft.com>
Date: Wed, 14 Jun 2023 21:44:51 -0700
Subject: [PATCH] PCI: hv: Add a per-bus mutex state_lock
In the case of fast device addition/removal, it's possible that
hv_eject_device_work() can start to run before create_root_hv_pci_bus()
starts to run; as a result, the pci_get_domain_bus_and_slot() in
hv_eject_device_work() can return a 'pdev' of NULL, and
hv_eject_device_work() can remove the 'hpdev', and immediately send a
message PCI_EJECTION_COMPLETE to the host, and the host immediately
unassigns the PCI device from the guest; meanwhile,
create_root_hv_pci_bus() and the PCI device driver can be probing the
dead PCI device and reporting timeout errors.
Fix the issue by adding a per-bus mutex 'state_lock' and grabbing the
mutex before powering on the PCI bus in hv_pci_enter_d0(): when
hv_eject_device_work() starts to run, it's able to find the 'pdev' and call
pci_stop_and_remove_bus_device(pdev): if the PCI device driver has
loaded, the PCI device driver's probe() function is already called in
create_root_hv_pci_bus() -> pci_bus_add_devices(), and now
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able
to call the PCI device driver's remove() function and remove the device
reliably; if the PCI device driver hasn't loaded yet, the function call
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able to
remove the PCI device reliably and the PCI device driver's probe()
function won't be called; if the PCI device driver's probe() is already
running (e.g., systemd-udev is loading the PCI device driver), it must
be holding the per-device lock, and after the probe() finishes and releases
the lock, hv_eject_device_work() -> pci_stop_and_remove_bus_device() is
able to proceed to remove the device reliably.
Fixes: 4daace0d8ce8 ("PCI: hv: Add paravirtual PCI front-end for Microsoft Hyper-V VMs")
Signed-off-by: Dexuan Cui <decui(a)microsoft.com>
Reviewed-by: Michael Kelley <mikelley(a)microsoft.com>
Acked-by: Lorenzo Pieralisi <lpieralisi(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20230615044451.5580-6-decui@microsoft.com
Signed-off-by: Wei Liu <wei.liu(a)kernel.org>
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 1a5296fad1c4..2d93d0c4f10d 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -489,7 +489,10 @@ struct hv_pcibus_device {
struct fwnode_handle *fwnode;
/* Protocol version negotiated with the host */
enum pci_protocol_version_t protocol_version;
+
+ struct mutex state_lock;
enum hv_pcibus_state state;
+
struct hv_device *hdev;
resource_size_t low_mmio_space;
resource_size_t high_mmio_space;
@@ -2605,6 +2608,8 @@ static void pci_devices_present_work(struct work_struct *work)
if (!dr)
return;
+ mutex_lock(&hbus->state_lock);
+
/* First, mark all existing children as reported missing. */
spin_lock_irqsave(&hbus->device_list_lock, flags);
list_for_each_entry(hpdev, &hbus->children, list_entry) {
@@ -2686,6 +2691,8 @@ static void pci_devices_present_work(struct work_struct *work)
break;
}
+ mutex_unlock(&hbus->state_lock);
+
kfree(dr);
}
@@ -2834,6 +2841,8 @@ static void hv_eject_device_work(struct work_struct *work)
hpdev = container_of(work, struct hv_pci_dev, wrk);
hbus = hpdev->hbus;
+ mutex_lock(&hbus->state_lock);
+
/*
* Ejection can come before or after the PCI bus has been set up, so
* attempt to find it and tear down the bus state, if it exists. This
@@ -2870,6 +2879,8 @@ static void hv_eject_device_work(struct work_struct *work)
put_pcichild(hpdev);
put_pcichild(hpdev);
/* hpdev has been freed. Do not use it any more. */
+
+ mutex_unlock(&hbus->state_lock);
}
/**
@@ -3636,6 +3647,7 @@ static int hv_pci_probe(struct hv_device *hdev,
return -ENOMEM;
hbus->bridge = bridge;
+ mutex_init(&hbus->state_lock);
hbus->state = hv_pcibus_init;
hbus->wslot_res_allocated = -1;
@@ -3745,9 +3757,11 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_irq_domain;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto free_irq_domain;
+ goto release_state_lock;
ret = hv_pci_allocate_bridge_windows(hbus);
if (ret)
@@ -3765,12 +3779,15 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_windows;
+ mutex_unlock(&hbus->state_lock);
return 0;
free_windows:
hv_pci_free_bridge_windows(hbus);
exit_d0:
(void) hv_pci_bus_exit(hdev, true);
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
free_irq_domain:
irq_domain_remove(hbus->irq_domain);
free_fwnode:
@@ -4020,20 +4037,26 @@ static int hv_pci_resume(struct hv_device *hdev)
if (ret)
goto out;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
ret = hv_send_resources_allocated(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
prepopulate_bars(hbus);
hv_pci_restore_msi_state(hbus);
hbus->state = hv_pcibus_installed;
+ mutex_unlock(&hbus->state_lock);
return 0;
+
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
out:
vmbus_close(hdev->channel);
return ret;
The patch below does not apply to the 4.19-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 067d6ec7ed5b49380688e06c1e5f883a71bef4fe
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062350-companion-debtless-8e8e@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 067d6ec7ed5b49380688e06c1e5f883a71bef4fe Mon Sep 17 00:00:00 2001
From: Dexuan Cui <decui(a)microsoft.com>
Date: Wed, 14 Jun 2023 21:44:51 -0700
Subject: [PATCH] PCI: hv: Add a per-bus mutex state_lock
In the case of fast device addition/removal, it's possible that
hv_eject_device_work() can start to run before create_root_hv_pci_bus()
starts to run; as a result, the pci_get_domain_bus_and_slot() in
hv_eject_device_work() can return a 'pdev' of NULL, and
hv_eject_device_work() can remove the 'hpdev', and immediately send a
message PCI_EJECTION_COMPLETE to the host, and the host immediately
unassigns the PCI device from the guest; meanwhile,
create_root_hv_pci_bus() and the PCI device driver can be probing the
dead PCI device and reporting timeout errors.
Fix the issue by adding a per-bus mutex 'state_lock' and grabbing the
mutex before powering on the PCI bus in hv_pci_enter_d0(): when
hv_eject_device_work() starts to run, it's able to find the 'pdev' and call
pci_stop_and_remove_bus_device(pdev): if the PCI device driver has
loaded, the PCI device driver's probe() function is already called in
create_root_hv_pci_bus() -> pci_bus_add_devices(), and now
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able
to call the PCI device driver's remove() function and remove the device
reliably; if the PCI device driver hasn't loaded yet, the function call
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able to
remove the PCI device reliably and the PCI device driver's probe()
function won't be called; if the PCI device driver's probe() is already
running (e.g., systemd-udev is loading the PCI device driver), it must
be holding the per-device lock, and after the probe() finishes and releases
the lock, hv_eject_device_work() -> pci_stop_and_remove_bus_device() is
able to proceed to remove the device reliably.
Fixes: 4daace0d8ce8 ("PCI: hv: Add paravirtual PCI front-end for Microsoft Hyper-V VMs")
Signed-off-by: Dexuan Cui <decui(a)microsoft.com>
Reviewed-by: Michael Kelley <mikelley(a)microsoft.com>
Acked-by: Lorenzo Pieralisi <lpieralisi(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20230615044451.5580-6-decui@microsoft.com
Signed-off-by: Wei Liu <wei.liu(a)kernel.org>
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 1a5296fad1c4..2d93d0c4f10d 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -489,7 +489,10 @@ struct hv_pcibus_device {
struct fwnode_handle *fwnode;
/* Protocol version negotiated with the host */
enum pci_protocol_version_t protocol_version;
+
+ struct mutex state_lock;
enum hv_pcibus_state state;
+
struct hv_device *hdev;
resource_size_t low_mmio_space;
resource_size_t high_mmio_space;
@@ -2605,6 +2608,8 @@ static void pci_devices_present_work(struct work_struct *work)
if (!dr)
return;
+ mutex_lock(&hbus->state_lock);
+
/* First, mark all existing children as reported missing. */
spin_lock_irqsave(&hbus->device_list_lock, flags);
list_for_each_entry(hpdev, &hbus->children, list_entry) {
@@ -2686,6 +2691,8 @@ static void pci_devices_present_work(struct work_struct *work)
break;
}
+ mutex_unlock(&hbus->state_lock);
+
kfree(dr);
}
@@ -2834,6 +2841,8 @@ static void hv_eject_device_work(struct work_struct *work)
hpdev = container_of(work, struct hv_pci_dev, wrk);
hbus = hpdev->hbus;
+ mutex_lock(&hbus->state_lock);
+
/*
* Ejection can come before or after the PCI bus has been set up, so
* attempt to find it and tear down the bus state, if it exists. This
@@ -2870,6 +2879,8 @@ static void hv_eject_device_work(struct work_struct *work)
put_pcichild(hpdev);
put_pcichild(hpdev);
/* hpdev has been freed. Do not use it any more. */
+
+ mutex_unlock(&hbus->state_lock);
}
/**
@@ -3636,6 +3647,7 @@ static int hv_pci_probe(struct hv_device *hdev,
return -ENOMEM;
hbus->bridge = bridge;
+ mutex_init(&hbus->state_lock);
hbus->state = hv_pcibus_init;
hbus->wslot_res_allocated = -1;
@@ -3745,9 +3757,11 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_irq_domain;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto free_irq_domain;
+ goto release_state_lock;
ret = hv_pci_allocate_bridge_windows(hbus);
if (ret)
@@ -3765,12 +3779,15 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_windows;
+ mutex_unlock(&hbus->state_lock);
return 0;
free_windows:
hv_pci_free_bridge_windows(hbus);
exit_d0:
(void) hv_pci_bus_exit(hdev, true);
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
free_irq_domain:
irq_domain_remove(hbus->irq_domain);
free_fwnode:
@@ -4020,20 +4037,26 @@ static int hv_pci_resume(struct hv_device *hdev)
if (ret)
goto out;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
ret = hv_send_resources_allocated(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
prepopulate_bars(hbus);
hv_pci_restore_msi_state(hbus);
hbus->state = hv_pcibus_installed;
+ mutex_unlock(&hbus->state_lock);
return 0;
+
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
out:
vmbus_close(hdev->channel);
return ret;
The patch below does not apply to the 5.4-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 067d6ec7ed5b49380688e06c1e5f883a71bef4fe
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062348-spout-suitcase-a356@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 067d6ec7ed5b49380688e06c1e5f883a71bef4fe Mon Sep 17 00:00:00 2001
From: Dexuan Cui <decui(a)microsoft.com>
Date: Wed, 14 Jun 2023 21:44:51 -0700
Subject: [PATCH] PCI: hv: Add a per-bus mutex state_lock
In the case of fast device addition/removal, it's possible that
hv_eject_device_work() can start to run before create_root_hv_pci_bus()
starts to run; as a result, the pci_get_domain_bus_and_slot() in
hv_eject_device_work() can return a 'pdev' of NULL, and
hv_eject_device_work() can remove the 'hpdev', and immediately send a
message PCI_EJECTION_COMPLETE to the host, and the host immediately
unassigns the PCI device from the guest; meanwhile,
create_root_hv_pci_bus() and the PCI device driver can be probing the
dead PCI device and reporting timeout errors.
Fix the issue by adding a per-bus mutex 'state_lock' and grabbing the
mutex before powering on the PCI bus in hv_pci_enter_d0(): when
hv_eject_device_work() starts to run, it's able to find the 'pdev' and call
pci_stop_and_remove_bus_device(pdev): if the PCI device driver has
loaded, the PCI device driver's probe() function is already called in
create_root_hv_pci_bus() -> pci_bus_add_devices(), and now
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able
to call the PCI device driver's remove() function and remove the device
reliably; if the PCI device driver hasn't loaded yet, the function call
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able to
remove the PCI device reliably and the PCI device driver's probe()
function won't be called; if the PCI device driver's probe() is already
running (e.g., systemd-udev is loading the PCI device driver), it must
be holding the per-device lock, and after the probe() finishes and releases
the lock, hv_eject_device_work() -> pci_stop_and_remove_bus_device() is
able to proceed to remove the device reliably.
Fixes: 4daace0d8ce8 ("PCI: hv: Add paravirtual PCI front-end for Microsoft Hyper-V VMs")
Signed-off-by: Dexuan Cui <decui(a)microsoft.com>
Reviewed-by: Michael Kelley <mikelley(a)microsoft.com>
Acked-by: Lorenzo Pieralisi <lpieralisi(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20230615044451.5580-6-decui@microsoft.com
Signed-off-by: Wei Liu <wei.liu(a)kernel.org>
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 1a5296fad1c4..2d93d0c4f10d 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -489,7 +489,10 @@ struct hv_pcibus_device {
struct fwnode_handle *fwnode;
/* Protocol version negotiated with the host */
enum pci_protocol_version_t protocol_version;
+
+ struct mutex state_lock;
enum hv_pcibus_state state;
+
struct hv_device *hdev;
resource_size_t low_mmio_space;
resource_size_t high_mmio_space;
@@ -2605,6 +2608,8 @@ static void pci_devices_present_work(struct work_struct *work)
if (!dr)
return;
+ mutex_lock(&hbus->state_lock);
+
/* First, mark all existing children as reported missing. */
spin_lock_irqsave(&hbus->device_list_lock, flags);
list_for_each_entry(hpdev, &hbus->children, list_entry) {
@@ -2686,6 +2691,8 @@ static void pci_devices_present_work(struct work_struct *work)
break;
}
+ mutex_unlock(&hbus->state_lock);
+
kfree(dr);
}
@@ -2834,6 +2841,8 @@ static void hv_eject_device_work(struct work_struct *work)
hpdev = container_of(work, struct hv_pci_dev, wrk);
hbus = hpdev->hbus;
+ mutex_lock(&hbus->state_lock);
+
/*
* Ejection can come before or after the PCI bus has been set up, so
* attempt to find it and tear down the bus state, if it exists. This
@@ -2870,6 +2879,8 @@ static void hv_eject_device_work(struct work_struct *work)
put_pcichild(hpdev);
put_pcichild(hpdev);
/* hpdev has been freed. Do not use it any more. */
+
+ mutex_unlock(&hbus->state_lock);
}
/**
@@ -3636,6 +3647,7 @@ static int hv_pci_probe(struct hv_device *hdev,
return -ENOMEM;
hbus->bridge = bridge;
+ mutex_init(&hbus->state_lock);
hbus->state = hv_pcibus_init;
hbus->wslot_res_allocated = -1;
@@ -3745,9 +3757,11 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_irq_domain;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto free_irq_domain;
+ goto release_state_lock;
ret = hv_pci_allocate_bridge_windows(hbus);
if (ret)
@@ -3765,12 +3779,15 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_windows;
+ mutex_unlock(&hbus->state_lock);
return 0;
free_windows:
hv_pci_free_bridge_windows(hbus);
exit_d0:
(void) hv_pci_bus_exit(hdev, true);
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
free_irq_domain:
irq_domain_remove(hbus->irq_domain);
free_fwnode:
@@ -4020,20 +4037,26 @@ static int hv_pci_resume(struct hv_device *hdev)
if (ret)
goto out;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
ret = hv_send_resources_allocated(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
prepopulate_bars(hbus);
hv_pci_restore_msi_state(hbus);
hbus->state = hv_pcibus_installed;
+ mutex_unlock(&hbus->state_lock);
return 0;
+
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
out:
vmbus_close(hdev->channel);
return ret;
The patch below does not apply to the 5.10-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 <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 067d6ec7ed5b49380688e06c1e5f883a71bef4fe
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023062346-consuming-staunch-e0a5@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 067d6ec7ed5b49380688e06c1e5f883a71bef4fe Mon Sep 17 00:00:00 2001
From: Dexuan Cui <decui(a)microsoft.com>
Date: Wed, 14 Jun 2023 21:44:51 -0700
Subject: [PATCH] PCI: hv: Add a per-bus mutex state_lock
In the case of fast device addition/removal, it's possible that
hv_eject_device_work() can start to run before create_root_hv_pci_bus()
starts to run; as a result, the pci_get_domain_bus_and_slot() in
hv_eject_device_work() can return a 'pdev' of NULL, and
hv_eject_device_work() can remove the 'hpdev', and immediately send a
message PCI_EJECTION_COMPLETE to the host, and the host immediately
unassigns the PCI device from the guest; meanwhile,
create_root_hv_pci_bus() and the PCI device driver can be probing the
dead PCI device and reporting timeout errors.
Fix the issue by adding a per-bus mutex 'state_lock' and grabbing the
mutex before powering on the PCI bus in hv_pci_enter_d0(): when
hv_eject_device_work() starts to run, it's able to find the 'pdev' and call
pci_stop_and_remove_bus_device(pdev): if the PCI device driver has
loaded, the PCI device driver's probe() function is already called in
create_root_hv_pci_bus() -> pci_bus_add_devices(), and now
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able
to call the PCI device driver's remove() function and remove the device
reliably; if the PCI device driver hasn't loaded yet, the function call
hv_eject_device_work() -> pci_stop_and_remove_bus_device() is able to
remove the PCI device reliably and the PCI device driver's probe()
function won't be called; if the PCI device driver's probe() is already
running (e.g., systemd-udev is loading the PCI device driver), it must
be holding the per-device lock, and after the probe() finishes and releases
the lock, hv_eject_device_work() -> pci_stop_and_remove_bus_device() is
able to proceed to remove the device reliably.
Fixes: 4daace0d8ce8 ("PCI: hv: Add paravirtual PCI front-end for Microsoft Hyper-V VMs")
Signed-off-by: Dexuan Cui <decui(a)microsoft.com>
Reviewed-by: Michael Kelley <mikelley(a)microsoft.com>
Acked-by: Lorenzo Pieralisi <lpieralisi(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20230615044451.5580-6-decui@microsoft.com
Signed-off-by: Wei Liu <wei.liu(a)kernel.org>
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 1a5296fad1c4..2d93d0c4f10d 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -489,7 +489,10 @@ struct hv_pcibus_device {
struct fwnode_handle *fwnode;
/* Protocol version negotiated with the host */
enum pci_protocol_version_t protocol_version;
+
+ struct mutex state_lock;
enum hv_pcibus_state state;
+
struct hv_device *hdev;
resource_size_t low_mmio_space;
resource_size_t high_mmio_space;
@@ -2605,6 +2608,8 @@ static void pci_devices_present_work(struct work_struct *work)
if (!dr)
return;
+ mutex_lock(&hbus->state_lock);
+
/* First, mark all existing children as reported missing. */
spin_lock_irqsave(&hbus->device_list_lock, flags);
list_for_each_entry(hpdev, &hbus->children, list_entry) {
@@ -2686,6 +2691,8 @@ static void pci_devices_present_work(struct work_struct *work)
break;
}
+ mutex_unlock(&hbus->state_lock);
+
kfree(dr);
}
@@ -2834,6 +2841,8 @@ static void hv_eject_device_work(struct work_struct *work)
hpdev = container_of(work, struct hv_pci_dev, wrk);
hbus = hpdev->hbus;
+ mutex_lock(&hbus->state_lock);
+
/*
* Ejection can come before or after the PCI bus has been set up, so
* attempt to find it and tear down the bus state, if it exists. This
@@ -2870,6 +2879,8 @@ static void hv_eject_device_work(struct work_struct *work)
put_pcichild(hpdev);
put_pcichild(hpdev);
/* hpdev has been freed. Do not use it any more. */
+
+ mutex_unlock(&hbus->state_lock);
}
/**
@@ -3636,6 +3647,7 @@ static int hv_pci_probe(struct hv_device *hdev,
return -ENOMEM;
hbus->bridge = bridge;
+ mutex_init(&hbus->state_lock);
hbus->state = hv_pcibus_init;
hbus->wslot_res_allocated = -1;
@@ -3745,9 +3757,11 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_irq_domain;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto free_irq_domain;
+ goto release_state_lock;
ret = hv_pci_allocate_bridge_windows(hbus);
if (ret)
@@ -3765,12 +3779,15 @@ static int hv_pci_probe(struct hv_device *hdev,
if (ret)
goto free_windows;
+ mutex_unlock(&hbus->state_lock);
return 0;
free_windows:
hv_pci_free_bridge_windows(hbus);
exit_d0:
(void) hv_pci_bus_exit(hdev, true);
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
free_irq_domain:
irq_domain_remove(hbus->irq_domain);
free_fwnode:
@@ -4020,20 +4037,26 @@ static int hv_pci_resume(struct hv_device *hdev)
if (ret)
goto out;
+ mutex_lock(&hbus->state_lock);
+
ret = hv_pci_enter_d0(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
ret = hv_send_resources_allocated(hdev);
if (ret)
- goto out;
+ goto release_state_lock;
prepopulate_bars(hbus);
hv_pci_restore_msi_state(hbus);
hbus->state = hv_pcibus_installed;
+ mutex_unlock(&hbus->state_lock);
return 0;
+
+release_state_lock:
+ mutex_unlock(&hbus->state_lock);
out:
vmbus_close(hdev->channel);
return ret;