The ring buffer size varies across VMBus channels. The size of sysfs
node for the ring buffer is currently hardcoded to 4 MB. Userspace
clients either use fstat() or hardcode this size for doing mmap().
To address this, make the sysfs node size dynamic to reflect the
actual ring buffer size for each channel. This will ensure that
fstat() on ring sysfs node always returns the correct size of
ring buffer.
This is a backport of the upstream commit
65995e97a1ca ("Drivers: hv: Make the sysfs node size for the ring buffer dynamic")
with modifications, as the original patch has missing dependencies on
kernel v6.12.x. The structure "struct attribute_group" does not have
bin_size field in v6.12.x kernel so the logic of configuring size of
sysfs node for ring buffer has been moved to
vmbus_chan_bin_attr_is_visible().
Original change was not a fix, but it needs to be backported to fix size
related discrepancy caused by the commit mentioned in Fixes tag.
Fixes: bf1299797c3c ("uio_hv_generic: Align ring size to system page")
Cc: <stable(a)vger.kernel.org> # 6.12.x
Signed-off-by: Naman Jain <namjain(a)linux.microsoft.com>
---
This change won't apply on older kernels currently due to missing
dependencies. I will take care of them after this goes in.
I did not retain any Reviewed-by or Tested-by tags, since the code has
changed completely, while the functionality remains same.
Requesting Michael, Dexuan, Wei to please review again.
---
drivers/hv/vmbus_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 1f519e925f06..616e63fb2f15 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1810,7 +1810,6 @@ static struct bin_attribute chan_attr_ring_buffer = {
.name = "ring",
.mode = 0600,
},
- .size = 2 * SZ_2M,
.mmap = hv_mmap_ring_buffer_wrapper,
};
static struct attribute *vmbus_chan_attrs[] = {
@@ -1866,6 +1865,7 @@ static umode_t vmbus_chan_bin_attr_is_visible(struct kobject *kobj,
/* Hide ring attribute if channel's ring_sysfs_visible is set to false */
if (attr == &chan_attr_ring_buffer && !channel->ring_sysfs_visible)
return 0;
+ attr->size = channel->ringbuffer_pagecount << PAGE_SHIFT;
return attr->attr.mode;
}
--
2.34.1
The gpio-mlxbf2 driver interfaces with four GPIO controllers,
device instances 0-3. There are two IRQ resources shared between
the four controllers, and they are found in the ACPI table for
instances 0 and 3. The driver should not use platform_get_irq(),
otherwise this error is logged when probing instances 1 and 2:
mlxbf2_gpio MLNXBF22:01: error -ENXIO: IRQ index 0 not found
Fixes: 2b725265cb08 ("gpio: mlxbf2: Introduce IRQ support")
Cc: stable(a)vger.kernel.org
Signed-off-by: David Thompson <davthompson(a)nvidia.com>
Reviewed-by: Shravan Kumar Ramani <shravankr(a)nvidia.com>
---
v4: updated logic to simply use platform_get_irq_optional()
v3: added version history
v2: added tag "Cc: stable(a)vger.kernel.org"
drivers/gpio/gpio-mlxbf2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
index 6f3dda6b635f..390f2e74a9d8 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -397,7 +397,7 @@ mlxbf2_gpio_probe(struct platform_device *pdev)
gc->ngpio = npins;
gc->owner = THIS_MODULE;
- irq = platform_get_irq(pdev, 0);
+ irq = platform_get_irq_optional(pdev, 0);
if (irq >= 0) {
girq = &gs->gc.irq;
gpio_irq_chip_set_chip(girq, &mlxbf2_gpio_irq_chip);
--
2.43.2
Increase the External ROM access timeouts to prevent failures during
programming of External SPI EEPROM chips. The current timeouts are
too short for some SPI EEPROMs used with uPD720201 controllers.
The current timeout for Chip Erase in renesas_rom_erase() is 100 ms ,
the current timeout for Sector Erase issued by the controller before
Page Program in renesas_fw_download_image() is also 100 ms. Neither
timeout is sufficient for e.g. the Macronix MX25L5121E or MX25V5126F.
MX25L5121E reference manual [1] page 35 section "ERASE AND PROGRAMMING
PERFORMANCE" and page 23 section "Table 8. AC CHARACTERISTICS (Temperature
= 0°C to 70°C for Commercial grade, VCC = 2.7V ~ 3.6V)" row "tCE" indicate
that the maximum time required for Chip Erase opcode to complete is 2 s,
and for Sector Erase it is 300 ms .
MX25V5126F reference manual [2] page 47 section "13. ERASE AND PROGRAMMING
PERFORMANCE (2.3V - 3.6V)" and page 42 section "Table 8. AC CHARACTERISTICS
(Temperature = -40°C to 85°C for Industrial grade, VCC = 2.3V - 3.6V)" row
"tCE" indicate that the maximum time required for Chip Erase opcode to
complete is 3.2 s, and for Sector Erase it is 400 ms .
Update the timeouts such, that Chip Erase timeout is set to 5 seconds,
and Sector Erase timeout is set to 500 ms. Such lengthy timeouts ought
to be sufficient for majority of SPI EEPROM chips.
[1] https://www.macronix.com/Lists/Datasheet/Attachments/8634/MX25L5121E,%203V,…
[2] https://www.macronix.com/Lists/Datasheet/Attachments/8750/MX25V5126F,%202.5…
Fixes: 2478be82de44 ("usb: renesas-xhci: Add ROM loader for uPD720201")
Signed-off-by: Marek Vasut <marek.vasut+renesas(a)mailbox.org>
---
Cc: Geert Uytterhoeven <geert+renesas(a)glider.be>
Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Cc: Mathias Nyman <mathias.nyman(a)intel.com>
Cc: Vinod Koul <vkoul(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Cc: linux-renesas-soc(a)vger.kernel.org
Cc: linux-usb(a)vger.kernel.org
---
drivers/usb/host/xhci-pci-renesas.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/host/xhci-pci-renesas.c b/drivers/usb/host/xhci-pci-renesas.c
index 620f8f0febb8..86df80399c9f 100644
--- a/drivers/usb/host/xhci-pci-renesas.c
+++ b/drivers/usb/host/xhci-pci-renesas.c
@@ -47,8 +47,9 @@
#define RENESAS_ROM_ERASE_MAGIC 0x5A65726F
#define RENESAS_ROM_WRITE_MAGIC 0x53524F4D
-#define RENESAS_RETRY 10000
-#define RENESAS_DELAY 10
+#define RENESAS_RETRY 50000 /* 50000 * RENESAS_DELAY ~= 500ms */
+#define RENESAS_CHIP_ERASE_RETRY 500000 /* 500000 * RENESAS_DELAY ~= 5s */
+#define RENESAS_DELAY 10
#define RENESAS_FW_NAME "renesas_usb_fw.mem"
@@ -407,7 +408,7 @@ static void renesas_rom_erase(struct pci_dev *pdev)
/* sleep a bit while ROM is erased */
msleep(20);
- for (i = 0; i < RENESAS_RETRY; i++) {
+ for (i = 0; i < RENESAS_CHIP_ERASE_RETRY; i++) {
retval = pci_read_config_byte(pdev, RENESAS_ROM_STATUS,
&status);
status &= RENESAS_ROM_STATUS_ERASE;
--
2.47.2
The patch that broke text mode VGA-console scrolling is this one:
"vgacon: Add check for vc_origin address range in vgacon_scroll()"
commit 864f9963ec6b4b76d104d595ba28110b87158003 upstream.
How to preproduce:
(1) boot a kernel that is configured to use text mode VGA-console
(2) type commands: ls -l /usr/bin | less -S
(3) scroll up/down with cursor-down/up keys
Above mentioned patch seems to have landed in upstream and all
kernel.org stable trees with zero testing. Even minimal testing
would have shown that it breaks text mode VGA-console scrolling.
Greg, Sasha, Linus,
Please consider reverting that buggy patch from all affected trees.
--
Jari Ruusu 4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD ACDF F073 3C80 8132 F189
Hello maintainers,
This series addresses a defect observed on certain hardware platforms using Linux kernel 6.1.147 with the i915 driver. The issue concerns hot plug detection (HPD) logic,
leading to unreliable or missed detection events on affected hardware. This is happening on some specific devices.
### Background
Issue:
On Simatic IPC227E, we observed unreliable or missing hot plug detection events, while on Simatic IPC227G (otherwise similar platform), expected hot plug behavior was maintained.
Affected kernel:
This patch series is intended for the Linux 6.1.y stable tree only (tested on 6.1.147)
Most of the tests were conducted on 6.1.147 (manual/standalone kernel build, CIP/Isar context).
Root cause analysis:
I do not have access to hardware signal traces or scope data to conclusively prove the root cause at electrical level. My understanding is based on observed driver behavior and logs.
Therefore my assumption as to the real cause is that on IPC227G, HPD IRQ storms are apparently not occurring, so the standard HPD IRQ-based detection works as expected. On IPC227E,
frequent HPD interrupts trigger the i915 driver’s storm detection logic, causing it to switch to polling mode. Therefore polling does not resume correctly, leading to the hotplug
issue this series addresses. Device IPC227E's behavior triggers this kernel edge case, likely due to slight variations in signal integrity, electrical margins, or internal component timing.
Device IPC227G, functions as expected, possibly due to cleaner electrical signaling or more optimal timing characteristics, thus avoiding the triggering condition.
Conclusion:
This points to a hardware-software interaction where kernel code assumes nicer signaling or margins than IPC227E is able to provide, exposing logic gaps not visible on more robust hardware.
### Patches
Patches 1-4:
- Partial backports of upstream commits; only the relevant logic or fixes are applied, with other code omitted due to downstream divergence.
- Applied minimal merging without exhaustive backport of all intermediate upstream changes.
Patch 5:
- Contains cherry-picked logic plus context/compatibility amendments as needed. Ensures that the driver builds.
- Together these fixes greatly improve reliability of hotplug detection on both devices, with no regression detected in our setups.
Thank you for your review,
Nicusor Huhulea
This patch series contains the following changes:
Dmitry Baryshkov (2):
drm/probe_helper: extract two helper functions
drm/probe-helper: enable and disable HPD on connectors
Imre Deak (2):
drm/i915: Fix HPD polling, reenabling the output poll work as needed
drm: Add an HPD poll helper to reschedule the poll work
Nicusor Huhulea (1):
drm/i915: fixes for i915 Hot Plug Detection and build/runtime issues
drivers/gpu/drm/drm_probe_helper.c | 127 ++++++++++++++-----
drivers/gpu/drm/i915/display/intel_hotplug.c | 4 +-
include/drm/drm_modeset_helper_vtables.h | 22 ++++
include/drm/drm_probe_helper.h | 1 +
4 files changed, 122 insertions(+), 32 deletions(-)
--
2.39.2
To prevent timing attacks, HMAC value comparison needs to be constant
time. Replace the memcmp() with the correct function, crypto_memneq().
Fixes: 1085b8276bb4 ("tpm: Add the rest of the session HMAC API")
Cc: stable(a)vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers(a)kernel.org>
---
drivers/char/tpm/Kconfig | 1 +
drivers/char/tpm/tpm2-sessions.c | 6 +++---
2 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
index dddd702b2454a..f9d8a4e966867 100644
--- a/drivers/char/tpm/Kconfig
+++ b/drivers/char/tpm/Kconfig
@@ -31,10 +31,11 @@ config TCG_TPM2_HMAC
bool "Use HMAC and encrypted transactions on the TPM bus"
default X86_64
select CRYPTO_ECDH
select CRYPTO_LIB_AESCFB
select CRYPTO_LIB_SHA256
+ select CRYPTO_LIB_UTILS
help
Setting this causes us to deploy a scheme which uses request
and response HMACs in addition to encryption for
communicating with the TPM to prevent or detect bus snooping
and interposer attacks (see tpm-security.rst). Saying Y
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index bdb119453dfbe..5fbd62ee50903 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -69,10 +69,11 @@
#include <linux/unaligned.h>
#include <crypto/kpp.h>
#include <crypto/ecdh.h>
#include <crypto/hash.h>
#include <crypto/hmac.h>
+#include <crypto/utils.h>
/* maximum number of names the TPM must remember for authorization */
#define AUTH_MAX_NAMES 3
#define AES_KEY_BYTES AES_KEYSIZE_128
@@ -827,16 +828,15 @@ int tpm_buf_check_hmac_response(struct tpm_chip *chip, struct tpm_buf *buf,
sha256_update(&sctx, auth->our_nonce, sizeof(auth->our_nonce));
sha256_update(&sctx, &auth->attrs, 1);
/* we're done with the rphash, so put our idea of the hmac there */
tpm2_hmac_final(&sctx, auth->session_key, sizeof(auth->session_key)
+ auth->passphrase_len, rphash);
- if (memcmp(rphash, &buf->data[offset_s], SHA256_DIGEST_SIZE) == 0) {
- rc = 0;
- } else {
+ if (crypto_memneq(rphash, &buf->data[offset_s], SHA256_DIGEST_SIZE)) {
dev_err(&chip->dev, "TPM: HMAC check failed\n");
goto out;
}
+ rc = 0;
/* now do response decryption */
if (auth->attrs & TPM2_SA_ENCRYPT) {
/* need key and IV */
tpm2_KDFa(auth->session_key, SHA256_DIGEST_SIZE
--
2.50.1
The Gemalto Cinterion PLS83-W modem (cdc_ether) is emitting confusing link
up and down events when the WWAN interface is activated on the modem-side.
Interrupt URBs will in consecutive polls grab:
* Link Connected
* Link Disconnected
* Link Connected
Where the last Connected is then a stable link state.
When the system is under load this may cause the unlink_urbs() work in
__handle_link_change() to not complete before the next usbnet_link_change()
call turns the carrier on again, allowing rx_submit() to queue new SKBs.
In that event the URB queue is filled faster than it can drain, ending up
in a RCU stall:
rcu: INFO: rcu_sched detected expedited stalls on CPUs/tasks: { 0-.... } 33108 jiffies s: 201 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
Call trace:
arch_local_irq_enable+0x4/0x8
local_bh_enable+0x18/0x20
__netdev_alloc_skb+0x18c/0x1cc
rx_submit+0x68/0x1f8 [usbnet]
rx_alloc_submit+0x4c/0x74 [usbnet]
usbnet_bh+0x1d8/0x218 [usbnet]
usbnet_bh_tasklet+0x10/0x18 [usbnet]
tasklet_action_common+0xa8/0x110
tasklet_action+0x2c/0x34
handle_softirqs+0x2cc/0x3a0
__do_softirq+0x10/0x18
____do_softirq+0xc/0x14
call_on_irq_stack+0x24/0x34
do_softirq_own_stack+0x18/0x20
__irq_exit_rcu+0xa8/0xb8
irq_exit_rcu+0xc/0x30
el1_interrupt+0x34/0x48
el1h_64_irq_handler+0x14/0x1c
el1h_64_irq+0x68/0x6c
_raw_spin_unlock_irqrestore+0x38/0x48
xhci_urb_dequeue+0x1ac/0x45c [xhci_hcd]
unlink1+0xd4/0xdc [usbcore]
usb_hcd_unlink_urb+0x70/0xb0 [usbcore]
usb_unlink_urb+0x24/0x44 [usbcore]
unlink_urbs.constprop.0.isra.0+0x64/0xa8 [usbnet]
__handle_link_change+0x34/0x70 [usbnet]
usbnet_deferred_kevent+0x1c0/0x320 [usbnet]
process_scheduled_works+0x2d0/0x48c
worker_thread+0x150/0x1dc
kthread+0xd8/0xe8
ret_from_fork+0x10/0x20
Get around the problem by delaying the carrier on to the scheduled work.
This needs a new flag to keep track of the necessary action.
The carrier ok check cannot be removed as it remains required for the
LINK_RESET event flow.
Fixes: 4b49f58fff00 ("usbnet: handle link change")
Cc: stable(a)vger.kernel.org
Signed-off-by: John Ernberg <john.ernberg(a)actia.se>
---
I've been testing this quite aggressively over a night, and seems equally
stable to my first approach. I'm a little bit concerned that the bit stuff
can now race (although much smaller) in the opposite direction, that a
carrier off can occur between test_and_clear_bit() and the carrier on
action in the handler. Leaving the carrier on when it shouldn't be.
v2:
- target tree in patch description.
- Drop Ming Lei from address list as their address bounces.
- Rework solution based on feedback by Jakub (let me know if you want a
Suggested-by tag, if we're keeping this direction)
v1: https://lore.kernel.org/netdev/20250710085028.1070922-1-john.ernberg@actia.…
Tested on 6.12.20 and forward ported. Stack trace from 6.12.20.
---
drivers/net/usb/usbnet.c | 11 ++++++++---
include/linux/usb/usbnet.h | 1 +
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index c04e715a4c2a..bc1d8631ffe0 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1122,6 +1122,9 @@ static void __handle_link_change(struct usbnet *dev)
* tx queue is stopped by netcore after link becomes off
*/
} else {
+ if (test_and_clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags))
+ netif_carrier_on(dev->net);
+
/* submitting URBs for reading packets */
tasklet_schedule(&dev->bh);
}
@@ -2009,10 +2012,12 @@ EXPORT_SYMBOL(usbnet_manage_power);
void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
{
/* update link after link is reseted */
- if (link && !need_reset)
- netif_carrier_on(dev->net);
- else
+ if (link && !need_reset) {
+ set_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
+ } else {
+ clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
netif_carrier_off(dev->net);
+ }
if (need_reset && link)
usbnet_defer_kevent(dev, EVENT_LINK_RESET);
diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index 0b9f1e598e3a..4bc6bb01a0eb 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -76,6 +76,7 @@ struct usbnet {
# define EVENT_LINK_CHANGE 11
# define EVENT_SET_RX_MODE 12
# define EVENT_NO_IP_ALIGN 13
+# define EVENT_LINK_CARRIER_ON 14
/* This one is special, as it indicates that the device is going away
* there are cyclic dependencies between tasklet, timer and bh
* that must be broken
--
2.49.0