There is an issue with ACPI overlay table removal specifically related
to I2C multiplexers.
Consider an ACPI SSDT Overlay that defines a PCA9548 I2C mux on an
existing I2C bus. When this table is loaded we see the creation of a
device for the overall PCA9548 chip and 8 further devices - one
i2c_adapter each for the mux channels. These are all bound to their
ACPI equivalents via an eventual invocation of acpi_bind_one().
When we unload the SSDT overlay we run into the problem. The ACPI
devices are deleted as normal via acpi_device_del_work_fn() and the
acpi_device_del_list.
However, the following warning and stack trace is output as the
deletion does not go smoothly:
------------[ cut here ]------------
kernfs: can not remove 'physical_node', no directory
WARNING: CPU: 1 PID: 11 at fs/kernfs/dir.c:1674 kernfs_remove_by_name_ns+0xb9/0xc0
Modules linked in:
CPU: 1 PID: 11 Comm: kworker/u128:0 Not tainted 6.8.0-rc6+ #1
Hardware name: congatec AG conga-B7E3/conga-B7E3, BIOS 5.13 05/16/2023
Workqueue: kacpi_hotplug acpi_device_del_work_fn
RIP: 0010:kernfs_remove_by_name_ns+0xb9/0xc0
Code: e4 00 48 89 ef e8 07 71 db ff 5b b8 fe ff ff ff 5d 41 5c 41 5d e9 a7 55 e4 00 0f 0b eb a6 48 c7 c7 f0 38 0d 9d e8 97 0a d5 ff <0f> 0b eb dc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffff9f864008fb28 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff8ef90a8d4940 RCX: 0000000000000000
RDX: ffff8f000e267d10 RSI: ffff8f000e25c780 RDI: ffff8f000e25c780
RBP: ffff8ef9186f9870 R08: 0000000000013ffb R09: 00000000ffffbfff
R10: 00000000ffffbfff R11: ffff8f000e0a0000 R12: ffff9f864008fb50
R13: ffff8ef90c93dd60 R14: ffff8ef9010d0958 R15: ffff8ef9186f98c8
FS: 0000000000000000(0000) GS:ffff8f000e240000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48f5253a08 CR3: 00000003cb82e000 CR4: 00000000003506f0
Call Trace:
<TASK>
? kernfs_remove_by_name_ns+0xb9/0xc0
? __warn+0x7c/0x130
? kernfs_remove_by_name_ns+0xb9/0xc0
? report_bug+0x171/0x1a0
? handle_bug+0x3c/0x70
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? kernfs_remove_by_name_ns+0xb9/0xc0
? kernfs_remove_by_name_ns+0xb9/0xc0
acpi_unbind_one+0x108/0x180
device_del+0x18b/0x490
? srso_return_thunk+0x5/0x5f
? srso_return_thunk+0x5/0x5f
device_unregister+0xd/0x30
i2c_del_adapter.part.0+0x1bf/0x250
i2c_mux_del_adapters+0xa1/0xe0
i2c_device_remove+0x1e/0x80
device_release_driver_internal+0x19a/0x200
bus_remove_device+0xbf/0x100
device_del+0x157/0x490
? __pfx_device_match_fwnode+0x10/0x10
? srso_return_thunk+0x5/0x5f
device_unregister+0xd/0x30
i2c_acpi_notify+0x10f/0x140
notifier_call_chain+0x58/0xd0
blocking_notifier_call_chain+0x3a/0x60
acpi_device_del_work_fn+0x85/0x1d0
process_one_work+0x134/0x2f0
worker_thread+0x2f0/0x410
? __pfx_worker_thread+0x10/0x10
kthread+0xe3/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2f/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
---[ end trace 0000000000000000 ]---
...
repeated 7 more times, 1 for each channel of the mux
...
The issue is that the binding of the ACPI devices to their peer I2C
adapters is not correctly cleaned up. Digging deeper into the issue we
see that the deletion order is such that the ACPI devices matching the
mux channel i2c adapters are deleted first during the SSDT overlay
removal. For each of the channels we see a call to i2c_acpi_notify()
with ACPI_RECONFIG_DEVICE_REMOVE but, because these devices are not
actually i2c_clients, nothing is done for them.
Later on, after each of the mux channels has been dealt with, we come
to delete the i2c_client representing the PCA9548 device. This is the
call stack we see above, whereby the kernel cleans up the i2c_client
including destruction of the mux and its channel adapters. At this
point we do attempt to unbind from the ACPI peers but those peers no
longer exist and so we hit the kernfs errors.
The fix is to augment i2c_acpi_notify() to handle i2c_adapters. But,
given that the life cycle of the adapters is linked to the i2c_client,
instead of deleting the i2c_adapters during the i2c_acpi_notify(), we
just trigger unbinding of the ACPI device from the adapter device, and
allow the clean up of the adapter to continue in the way it always has.
Signed-off-by: Hamish Martin <hamish.martin(a)alliedtelesis.co.nz>
Reviewed-by: Mika Westerberg <mika.westerberg(a)linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti(a)kernel.org>
Fixes: 525e6fabeae2 ("i2c / ACPI: add support for ACPI reconfigure notifications")
Cc: <stable(a)vger.kernel.org> # v4.8+
---
Notes:
v4:
Resolve Build failure noted by:
Linux Kernel Functional Testing <lkft(a)linaro.org>, and
kernel test robot <lkp(a)intel.com>
These failures led to revert of the v3 version of this patch that had been accepted earlier.
v3:
Add reviewed by tags (Mika Westerberg and Andi Shyti) and Fixes tag.
v2:
Moved long problem description from cover letter to commit description at Mika's suggestion
drivers/i2c/i2c-core-acpi.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index d6037a328669..14ae0cfc325e 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -445,6 +445,11 @@ static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
return i2c_find_device_by_fwnode(acpi_fwnode_handle(adev));
}
+static struct i2c_adapter *i2c_acpi_find_adapter_by_adev(struct acpi_device *adev)
+{
+ return i2c_find_adapter_by_fwnode(acpi_fwnode_handle(adev));
+}
+
static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
void *arg)
{
@@ -471,11 +476,17 @@ static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
break;
client = i2c_acpi_find_client_by_adev(adev);
- if (!client)
- break;
+ if (client) {
+ i2c_unregister_device(client);
+ put_device(&client->dev);
+ }
+
+ adapter = i2c_acpi_find_adapter_by_adev(adev);
+ if (adapter) {
+ acpi_unbind_one(&adapter->dev);
+ put_device(&adapter->dev);
+ }
- i2c_unregister_device(client);
- put_device(&client->dev);
break;
}
--
2.43.2
Commit 5ec27ec735ba ("fs/proc/proc_sysctl.c: fix the default values of i_uid/i_gid on /proc/sys inodes.")
added defaults for i_uid/i_gid when set_ownership() is not implemented.
It missed to also adjust net_ctl_set_ownership() to use the same default
values in case the computation of a better value fails.
Instead always initialize i_uid/i_gid inside the sysfs core so
set_ownership() can safely skip setting them.
Fixes: 5ec27ec735ba ("fs/proc/proc_sysctl.c: fix the default values of i_uid/i_gid on /proc/sys inodes.")
Cc: stable(a)vger.kernel.org
Signed-off-by: Thomas Weißschuh <linux(a)weissschuh.net>
---
Changes in v3:
- Rebase onto v6.9-rc1
- Reword commit message and mention correct fixed commit
- Link to v2: https://lore.kernel.org/r/20240322-sysctl-net-ownership-v2-1-a8b4a3306542@w…
Changes in v2:
- Move the fallback logic to the sysctl core
- Link to v1: https://lore.kernel.org/r/20240315-sysctl-net-ownership-v1-1-2b465555a292@w…
---
fs/proc/proc_sysctl.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 37cde0efee57..9e34ab9c21e4 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -479,12 +479,10 @@ static struct inode *proc_sys_make_inode(struct super_block *sb,
make_empty_dir_inode(inode);
}
+ inode->i_uid = GLOBAL_ROOT_UID;
+ inode->i_gid = GLOBAL_ROOT_GID;
if (root->set_ownership)
root->set_ownership(head, table, &inode->i_uid, &inode->i_gid);
- else {
- inode->i_uid = GLOBAL_ROOT_UID;
- inode->i_gid = GLOBAL_ROOT_GID;
- }
return inode;
}
---
base-commit: 4cece764965020c22cff7665b18a012006359095
change-id: 20240315-sysctl-net-ownership-bc4e17eaeea6
Best regards,
--
Thomas Weißschuh <linux(a)weissschuh.net>
This reverts commit ad6bcdad2b6724e113f191a12f859a9e8456b26d. I had
nak'd it, and Greg said on the thread that it links that he wasn't going
to take it either, especially since it's not his code or his tree, but
then, seemingly accidentally, it got pushed up some months later, in
what looks like a mistake, with no further discussion in the linked
thread. So revert it, since it's clearly not intended.
Fixes: ad6bcdad2b67 ("vmgenid: emit uevent when VMGENID updates")
Cc: stable(a)vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Link: https://lore.kernel.org/r/20230531095119.11202-2-bchalios@amazon.es
Signed-off-by: Jason A. Donenfeld <Jason(a)zx2c4.com>
---
drivers/virt/vmgenid.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/virt/vmgenid.c b/drivers/virt/vmgenid.c
index b67a28da4702..a1c467a0e9f7 100644
--- a/drivers/virt/vmgenid.c
+++ b/drivers/virt/vmgenid.c
@@ -68,7 +68,6 @@ static int vmgenid_add(struct acpi_device *device)
static void vmgenid_notify(struct acpi_device *device, u32 event)
{
struct vmgenid_state *state = acpi_driver_data(device);
- char *envp[] = { "NEW_VMGENID=1", NULL };
u8 old_id[VMGENID_SIZE];
memcpy(old_id, state->this_id, sizeof(old_id));
@@ -76,7 +75,6 @@ static void vmgenid_notify(struct acpi_device *device, u32 event)
if (!memcmp(old_id, state->this_id, sizeof(old_id)))
return;
add_vmfork_randomness(state->this_id, sizeof(state->this_id));
- kobject_uevent_env(&device->dev.kobj, KOBJ_CHANGE, envp);
}
static const struct acpi_device_id vmgenid_ids[] = {
--
2.44.0
From: Vitor Soares <vitor.soares(a)toradex.com>
When the mcp251xfd_start_xmit() function fails, the driver stops
processing messages, and the interrupt routine does not return,
running indefinitely even after killing the running application.
Error messages:
[ 441.298819] mcp251xfd spi2.0 can0: ERROR in mcp251xfd_start_xmit: -16
[ 441.306498] mcp251xfd spi2.0 can0: Transmit Event FIFO buffer not empty. (seq=0x000017c7, tef_tail=0x000017cf, tef_head=0x000017d0, tx_head=0x000017d3).
... and repeat forever.
The issue can be triggered when multiple devices share the same
SPI interface. And there is concurrent access to the bus.
The problem occurs because tx_ring->head increments even if
mcp251xfd_start_xmit() fails. Consequently, the driver skips one
TX package while still expecting a response in
mcp251xfd_handle_tefif_one().
This patch resolves the issue by decreasing tx_ring->head if
mcp251xfd_start_xmit() fails. With the fix, if we trigger the issue and
the err = -EBUSY, the driver returns NETDEV_TX_BUSY. The network stack
retries to transmit the message.
Otherwise, it prints an error and discards the message.
Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Cc: stable(a)vger.kernel.org
Signed-off-by: Vitor Soares <vitor.soares(a)toradex.com>
---
V2->V3:
- Add tx_dropped stats.
- netdev_sent_queue() only if can_put_echo_skb() succeed.
V1->V2:
- Return NETDEV_TX_BUSY if mcp251xfd_tx_obj_write() == -EBUSY.
- Rework the commit message to address the change above.
- Change can_put_echo_skb() to be called after mcp251xfd_tx_obj_write() succeed.
Otherwise, we get Kernel NULL pointer dereference error.
drivers/net/can/spi/mcp251xfd/mcp251xfd-tx.c | 34 ++++++++++++--------
1 file changed, 21 insertions(+), 13 deletions(-)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-tx.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-tx.c
index 160528d3cc26..146c44e47c60 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-tx.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-tx.c
@@ -166,6 +166,7 @@ netdev_tx_t mcp251xfd_start_xmit(struct sk_buff *skb,
struct net_device *ndev)
{
struct mcp251xfd_priv *priv = netdev_priv(ndev);
+ struct net_device_stats *stats = &ndev->stats;
struct mcp251xfd_tx_ring *tx_ring = priv->tx;
struct mcp251xfd_tx_obj *tx_obj;
unsigned int frame_len;
@@ -181,25 +182,32 @@ netdev_tx_t mcp251xfd_start_xmit(struct sk_buff *skb,
tx_obj = mcp251xfd_get_tx_obj_next(tx_ring);
mcp251xfd_tx_obj_from_skb(priv, tx_obj, skb, tx_ring->head);
- /* Stop queue if we occupy the complete TX FIFO */
tx_head = mcp251xfd_get_tx_head(tx_ring);
- tx_ring->head++;
- if (mcp251xfd_get_tx_free(tx_ring) == 0)
- netif_stop_queue(ndev);
-
frame_len = can_skb_get_frame_len(skb);
- err = can_put_echo_skb(skb, ndev, tx_head, frame_len);
- if (!err)
- netdev_sent_queue(priv->ndev, frame_len);
+
+ tx_ring->head++;
err = mcp251xfd_tx_obj_write(priv, tx_obj);
- if (err)
- goto out_err;
+ if (err) {
+ tx_ring->head--;
- return NETDEV_TX_OK;
+ if (err == -EBUSY)
+ return NETDEV_TX_BUSY;
- out_err:
- netdev_err(priv->ndev, "ERROR in %s: %d\n", __func__, err);
+ stats->tx_dropped++;
+
+ if (net_ratelimit())
+ netdev_err(priv->ndev,
+ "ERROR in %s: %d\n", __func__, err);
+ } else {
+ err = can_put_echo_skb(skb, ndev, tx_head, frame_len);
+ if (!err)
+ netdev_sent_queue(priv->ndev, frame_len);
+
+ /* Stop queue if we occupy the complete TX FIFO */
+ if (mcp251xfd_get_tx_free(tx_ring) == 0)
+ netif_stop_queue(ndev);
+ }
return NETDEV_TX_OK;
}
--
2.34.1
This reverts commit 484fd6c1de13b336806a967908a927cc0356e312. The
commit caused a regression because now the umask was applied to
symlinks and the fix is unnecessary because the umask/O_TMPFILE bug
has been fixed somewhere else already.
Fixes: https://lore.kernel.org/lkml/28DSITL9912E1.2LSZUVTGTO52Q@mforney.org/
Signed-off-by: Max Kellermann <max.kellermann(a)ionos.com>
---
fs/ext4/acl.h | 5 -----
1 file changed, 5 deletions(-)
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
index ef4c19e5f570..0c5a79c3b5d4 100644
--- a/fs/ext4/acl.h
+++ b/fs/ext4/acl.h
@@ -68,11 +68,6 @@ extern int ext4_init_acl(handle_t *, struct inode *, struct inode *);
static inline int
ext4_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
{
- /* usually, the umask is applied by posix_acl_create(), but if
- ext4 ACL support is disabled at compile time, we need to do
- it here, because posix_acl_create() will never be called */
- inode->i_mode &= ~current_umask();
-
return 0;
}
#endif /* CONFIG_EXT4_FS_POSIX_ACL */
--
2.39.2