If a new reset event appears before the previous one has been
processed, the device can get stuck into a reset loop. This happens
rarely, but blocks the device when it does, and floods the log with
messages like the following:
lan78xx 2-3:1.0 enp1s0u3: kevent 4 may have been dropped
The only bit that the driver pays attention to in the interrupt data
is "link was reset". If there's a flapping status bit in that endpoint
data (such as if PHY negotiation needs a few tries to get a stable
link), polling at a slower rate allows the state to settle.
This is a simplified version of a patch that's been in the Raspberry
Pi downstream kernel since their 4.14 branch, see also:
https://github.com/raspberrypi/linux/issues/2447
Signed-off-by: Fiona Klute <fiona.klute(a)gmx.de>
Cc: kernel-list(a)raspberrypi.com
Cc: stable(a)vger.kernel.org
---
For the stable crew: I've *tested* the patch with 6.12.7 and 6.13.5 on
a Revolution Pi Connect 4 (Raspberry Pi CM4 based device with built-in
LAN7800 as second ethernet port), according to the linked issue for
the RPi downstream kernel the problem should be present in all
maintained longterm kernel versions, too (based on how long they've
carried a patch).
drivers/net/usb/lan78xx.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index a91bf9c7e31d..7bf01a31a932 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -173,6 +173,12 @@
#define INT_EP_GPIO_1 (1)
#define INT_EP_GPIO_0 (0)
+/* highspeed device, so polling interval is in microframes (eight per
+ * millisecond)
+ */
+#define INT_URB_MICROFRAMES_PER_MS 8
+#define MIN_INT_URB_INTERVAL_MS 8
+
static const char lan78xx_gstrings[][ETH_GSTRING_LEN] = {
"RX FCS Errors",
"RX Alignment Errors",
@@ -4527,7 +4533,11 @@ static int lan78xx_probe(struct usb_interface *intf,
if (ret < 0)
goto out4;
- period = ep_intr->desc.bInterval;
+ period = max(ep_intr->desc.bInterval,
+ MIN_INT_URB_INTERVAL_MS * INT_URB_MICROFRAMES_PER_MS);
+ dev_info(&intf->dev,
+ "interrupt urb period set to %d, bInterval is %d\n",
+ period, ep_intr->desc.bInterval);
maxp = usb_maxpacket(dev->udev, dev->pipe_intr);
dev->urb_intr = usb_alloc_urb(0, GFP_KERNEL);
base-commit: dd83757f6e686a2188997cb58b5975f744bb7786
--
2.47.2
Starting with Rust 1.86.0 (see upstream commit b151b513ba2b ("Insert null
checks for pointer dereferences when debug assertions are enabled") [1]),
under some kernel configurations with `CONFIG_RUST_DEBUG_ASSERTIONS=y`,
one may trigger a new `objtool` warning:
rust/kernel.o: warning: objtool: _R..._6kernel9workqueue6system()
falls through to next function _R...9workqueue14system_highpri()
due to a call to the `noreturn` symbol:
core::panicking::panic_null_pointer_dereference
Thus add it to the list so that `objtool` knows it is actually `noreturn`.
See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
for more details.
Cc: stable(a)vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Fixes: 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
Link: https://github.com/rust-lang/rust/commit/b151b513ba2b65c7506ec1a80f2712bbd0… [1]
Signed-off-by: Miguel Ojeda <ojeda(a)kernel.org>
---
tools/objtool/check.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 4a1f6c3169b3..67006eeb30c8 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -225,6 +225,7 @@ static bool is_rust_noreturn(const struct symbol *func)
str_ends_with(func->name, "_4core9panicking14panic_nounwind") ||
str_ends_with(func->name, "_4core9panicking18panic_bounds_check") ||
str_ends_with(func->name, "_4core9panicking19assert_failed_inner") ||
+ str_ends_with(func->name, "_4core9panicking30panic_null_pointer_dereference") ||
str_ends_with(func->name, "_4core9panicking36panic_misaligned_pointer_dereference") ||
strstr(func->name, "_4core9panicking13assert_failed") ||
strstr(func->name, "_4core9panicking11panic_const24panic_const_") ||
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
--
2.49.0