The DW UART may trigger the RX_TIMEOUT interrupt without data
present and remain stuck in this state indefinitely. The
dw8250_handle_irq() function detects this condition by checking
if the UART_LSR_DR bit is not set when RX_TIMEOUT occurs. When
detected, it performs a "dummy read" to recover the DW UART from
this state.
When the PSLVERR_RESP_EN parameter is set to 1, reading the UART_RX
while the FIFO is enabled and UART_LSR_DR is not set will generate a
PSLVERR error, which may lead to a system panic. There are two methods
to prevent PSLVERR: one is to check if UART_LSR_DR is set before reading
UART_RX when the FIFO is enabled, and the other is to read UART_RX when
the FIFO is disabled.
Given these two scenarios, the FIFO must be disabled before the
"dummy read" operation and re-enabled afterward to maintain normal
UART functionality.
Fixes: 424d79183af0 ("serial: 8250_dw: Avoid "too much work" from bogus rx timeout interrupt")
Signed-off-by: Yunhui Cui <cuiyunhui(a)bytedance.com>
Cc: stable(a)vger.kernel.org
---
drivers/tty/serial/8250/8250_dw.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 1902f29444a1c..082b7fcf251db 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -297,9 +297,17 @@ static int dw8250_handle_irq(struct uart_port *p)
uart_port_lock_irqsave(p, &flags);
status = serial_lsr_in(up);
- if (!(status & (UART_LSR_DR | UART_LSR_BI)))
+ if (!(status & (UART_LSR_DR | UART_LSR_BI))) {
+ /* To avoid PSLVERR, disable the FIFO first. */
+ if (up->fcr & UART_FCR_ENABLE_FIFO)
+ serial_out(up, UART_FCR, 0);
+
serial_port_in(p, UART_RX);
+ if (up->fcr & UART_FCR_ENABLE_FIFO)
+ serial_out(up, UART_FCR, up->fcr);
+ }
+
uart_port_unlock_irqrestore(p, flags);
}
--
2.39.5
Control: tag -1 + fixed-upstream
Control: forwarded -1 https://lore.kernel.org/r/20250530221824.work.623-kees@kernel.org
Hello,
On Mon, May 05, 2025 at 05:40:57PM +0200, Ingo Saitz wrote:
> When compiling the linux kernel (tested on 6.15-rc5 and 6.14.5 from
> kernel.org) with CONFIG_RANDSTRUCT enabled, gcc-15 throws an ICE:
>
> arch/x86/kernel/cpu/proc.c:174:14: internal compiler error: in comptypes_check_enum_int, at c/c-typeck.cc:1516
> 174 | const struct seq_operations cpuinfo_op = {
> | ^~~~~~~~~~~~~~
This is claimed to be fixed in upstream by commit
https://git.kernel.org/linus/f39f18f3c3531aa802b58a20d39d96e82eb96c14
that is scheduled to be included in 6.16-rc1.
This wasn't explicitly marked for stable, but I think a backport would
be good.
Best regards
Uwe
In 6.1/6.6 there is no BACKLIGHT_POWER_ON definition so a build error
occurs due to recently backport:
CC drivers/platform/loongarch/loongson-laptop.o
drivers/platform/loongarch/loongson-laptop.c: In function 'laptop_backlight_register':
drivers/platform/loongarch/loongson-laptop.c:428:23: error: 'BACKLIGHT_POWER_ON' undeclared (first use in this function)
428 | props.power = BACKLIGHT_POWER_ON;
| ^~~~~~~~~~~~~~~~~~
Use FB_BLANK_UNBLANK instead which has the same meaning.
Signed-off-by: Huacai Chen <chenhuacai(a)loongson.cn>
---
drivers/platform/loongarch/loongson-laptop.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/platform/loongarch/loongson-laptop.c b/drivers/platform/loongarch/loongson-laptop.c
index 61b18ac206c9..5fcfa3a7970b 100644
--- a/drivers/platform/loongarch/loongson-laptop.c
+++ b/drivers/platform/loongarch/loongson-laptop.c
@@ -425,7 +425,7 @@ static int laptop_backlight_register(void)
props.max_brightness = status;
props.brightness = ec_get_brightness();
- props.power = BACKLIGHT_POWER_ON;
+ props.power = FB_BLANK_UNBLANK;
props.type = BACKLIGHT_PLATFORM;
backlight_device_register("loongson_laptop",
--
2.47.1
During the High-Speed Isochronous Audio transfers, xHCI
controller on certain AMD platforms experiences momentary data
loss. This results in Missed Service Errors (MSE) being
generated by the xHCI.
The root cause of the MSE is attributed to the ISOC OUT endpoint
being omitted from scheduling. This can happen when an IN
endpoint with a 64ms service interval either is pre-scheduled
prior to the ISOC OUT endpoint or the interval of the ISOC OUT
endpoint is shorter than that of the IN endpoint. Consequently,
the OUT service is neglected when an IN endpoint with a service
interval exceeding 32ms is scheduled concurrently (every 64ms in
this scenario).
This issue is particularly seen on certain older AMD platforms.
To mitigate this problem, it is recommended to adjust the service
interval of the IN endpoint to not exceed 32ms (interval 8). This
adjustment ensures that the OUT endpoint will not be bypassed,
even if a smaller interval value is utilized.
Cc: stable(a)vger.kernel.org
Signed-off-by: Raju Rangoju <Raju.Rangoju(a)amd.com>
---
Changes since v4:
- reword the commit message.
- handle the potential corner case with ISOC IN ep with 64ms ESIT
Changes since v3:
- Bump up the enum number XHCI_LIMIT_ENDPOINT_INTERVAL_9
Changes since v2:
- added stable tag to backport to all stable kernels
Changes since v1:
- replaced hex values with pci device names
- corrected the commit message
---
drivers/usb/host/xhci-mem.c | 4 ++++
drivers/usb/host/xhci-pci.c | 25 +++++++++++++++++++++++++
drivers/usb/host/xhci.h | 1 +
3 files changed, 30 insertions(+)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index bd745a0f2f78..6680afa4f596 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1449,6 +1449,10 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
/* Periodic endpoint bInterval limit quirk */
if (usb_endpoint_xfer_int(&ep->desc) ||
usb_endpoint_xfer_isoc(&ep->desc)) {
+ if ((xhci->quirks & XHCI_LIMIT_ENDPOINT_INTERVAL_9) &&
+ interval >= 9) {
+ interval = 8;
+ }
if ((xhci->quirks & XHCI_LIMIT_ENDPOINT_INTERVAL_7) &&
udev->speed >= USB_SPEED_HIGH &&
interval >= 7) {
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 0c481cbc8f08..00fac8b233d2 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -71,12 +71,22 @@
#define PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_XHCI 0x15ec
#define PCI_DEVICE_ID_INTEL_TITAN_RIDGE_DD_XHCI 0x15f0
+#define PCI_DEVICE_ID_AMD_ARIEL_TYPEC_XHCI 0x13ed
+#define PCI_DEVICE_ID_AMD_ARIEL_TYPEA_XHCI 0x13ee
+#define PCI_DEVICE_ID_AMD_STARSHIP_XHCI 0x148c
+#define PCI_DEVICE_ID_AMD_FIREFLIGHT_15D4_XHCI 0x15d4
+#define PCI_DEVICE_ID_AMD_FIREFLIGHT_15D5_XHCI 0x15d5
+#define PCI_DEVICE_ID_AMD_RAVEN_15E0_XHCI 0x15e0
+#define PCI_DEVICE_ID_AMD_RAVEN_15E1_XHCI 0x15e1
+#define PCI_DEVICE_ID_AMD_RAVEN2_XHCI 0x15e5
#define PCI_DEVICE_ID_AMD_RENOIR_XHCI 0x1639
#define PCI_DEVICE_ID_AMD_PROMONTORYA_4 0x43b9
#define PCI_DEVICE_ID_AMD_PROMONTORYA_3 0x43ba
#define PCI_DEVICE_ID_AMD_PROMONTORYA_2 0x43bb
#define PCI_DEVICE_ID_AMD_PROMONTORYA_1 0x43bc
+#define PCI_DEVICE_ID_ATI_NAVI10_7316_XHCI 0x7316
+
#define PCI_DEVICE_ID_ASMEDIA_1042_XHCI 0x1042
#define PCI_DEVICE_ID_ASMEDIA_1042A_XHCI 0x1142
#define PCI_DEVICE_ID_ASMEDIA_1142_XHCI 0x1242
@@ -280,6 +290,21 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
if (pdev->vendor == PCI_VENDOR_ID_NEC)
xhci->quirks |= XHCI_NEC_HOST;
+ if (pdev->vendor == PCI_VENDOR_ID_AMD &&
+ (pdev->device == PCI_DEVICE_ID_AMD_ARIEL_TYPEC_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_ARIEL_TYPEA_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_STARSHIP_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_FIREFLIGHT_15D4_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_FIREFLIGHT_15D5_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_RAVEN_15E0_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_RAVEN_15E1_XHCI ||
+ pdev->device == PCI_DEVICE_ID_AMD_RAVEN2_XHCI))
+ xhci->quirks |= XHCI_LIMIT_ENDPOINT_INTERVAL_9;
+
+ if (pdev->vendor == PCI_VENDOR_ID_ATI &&
+ pdev->device == PCI_DEVICE_ID_ATI_NAVI10_7316_XHCI)
+ xhci->quirks |= XHCI_LIMIT_ENDPOINT_INTERVAL_9;
+
if (pdev->vendor == PCI_VENDOR_ID_AMD && xhci->hci_version == 0x96)
xhci->quirks |= XHCI_AMD_0x96_HOST;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 49887a303e43..ef7eaabc12fd 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1643,6 +1643,7 @@ struct xhci_hcd {
#define XHCI_WRITE_64_HI_LO BIT_ULL(47)
#define XHCI_CDNS_SCTX_QUIRK BIT_ULL(48)
#define XHCI_ETRON_HOST BIT_ULL(49)
+#define XHCI_LIMIT_ENDPOINT_INTERVAL_9 BIT_ULL(50)
unsigned int num_active_eps;
unsigned int limit_active_eps;
--
2.34.1
Hello,
we're facing a regression after updating to 5.15.179+.
I've found that fbdee71bb5d8d054e1bdb5af4c540f2cb86fe296 (block: deprecate autoloading based on dev_t) was merged that disabled autoloading of modules.
This broke mounting loopback devices on our side.
Why wasn't 451f0b6f4c44d7b649ae609157b114b71f6d7875 (block: default BLOCK_LEGACY_AUTOLOAD to y) merged, too?
This commit was merged for 6.1.y, 6.6.y and 6.12y, but not for 5.15.y.
Please consider merging this for 5.15.y soon.
Thanks.
Sebastian
From: Marek Vasut <marex(a)denx.de>
[ Upstream commit 8bad8c923f217d238ba4f1a6d19d761e53bfbd26 ]
The VSELECT pin is configured as MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT
and not as a GPIO, drop the bogus sd-vsel-gpios property as the eSDHC
block handles the VSELECT pin on its own.
Signed-off-by: Marek Vasut <marex(a)denx.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf(a)kontron.de>
Signed-off-by: Shawn Guo <shawnguo(a)kernel.org>
Signed-off-by: Francesco Dolcini <francesco.dolcini(a)toradex.com>
---
6.1.y is currently broken on imx8mm-verdin, because commit
5591ce0069ddda97cdbbea596bed53e698f399c2, that was backported correctly on 6.1,
depends on this one.
This fixes the following error:
[ 1.735149] gpio-regulator: probe of regulator-usdhc2-vqmmc failed with error -16
v2: add missing s-o-b francesco
---
arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
index 5b2493bb8dd9..37acaf62f5c7 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
@@ -362,7 +362,6 @@ pca9450: pmic@25 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_pmic>;
reg = <0x25>;
- sd-vsel-gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
/*
* The bootloader is expected to switch on the I2C level shifter for the TLA2024 ADC
--
2.39.5
Hello,
Please consider this series for 6.1.y
This patch series backports two patches that implement a test to verify
that a symbol with KSYM_NAME_LEN of 512 can be read.
The first patch implements the test. This commit also includes a fix
for the test x86/insn_decoder_test. In the case a symbol exceeds the
symbol length limit, an error will happen:
arch/x86/tools/insn_decoder_test: error: malformed line 1152000:
tBb_+0xf2>
..which overflowed by 10 characters reading this line:
ffffffff81458193: 74 3d je
ffffffff814581d2
<_RNvXse_NtNtNtCshGpAVYOtgW1_4core4iter8adapters7flattenINtB5_13FlattenCompatINtNtB7_3map3MapNtNtNtBb_3str4iter5CharsNtB1v_17CharEscapeDefaultENtNtBb_4char13EscapeDefaultENtNtBb_3fmt5Debug3fmtBb_+0xf2>
The fix was proposed in [1] and initially mentioned at [2].
The second patch fixes a warning when building with clang because
there was a definition of unlikely from compiler.h in tools/include/linux,
which conflicted with the one in the instruction decoder selftest.
[1] https://lore.kernel.org/lkml/Y9ES4UKl%2F+DtvAVS@gmail.com/
[2] https://lore.kernel.org/lkml/320c4dba-9919-404b-8a26-a8af16be1845@app.fastm…
Thanks,
Sergio
Nathan Chancellor (1):
x86/tools: Drop duplicate unlikely() definition in insn_decoder_test.c
Sergio González Collado (1):
Kunit to check the longest symbol length
arch/x86/tools/insn_decoder_test.c | 5 +-
lib/Kconfig.debug | 9 ++++
lib/Makefile | 2 +
lib/longest_symbol_kunit.c | 82 ++++++++++++++++++++++++++++++
4 files changed, 95 insertions(+), 3 deletions(-)
create mode 100644 lib/longest_symbol_kunit.c
base-commit: 58485ff1a74f6c5be9e7c6aafb7293e4337348e7
--
2.39.2
Hello,
Please consider this series for 6.6.y
This patch series backports two patches that implement a test to verify
that a symbol with KSYM_NAME_LEN of 512 can be read.
The first patch implements the test. This commit also includes a fix
for the test x86/insn_decoder_test. In the case a symbol exceeds the
symbol length limit, an error will happen:
arch/x86/tools/insn_decoder_test: error: malformed line 1152000:
tBb_+0xf2>
..which overflowed by 10 characters reading this line:
ffffffff81458193: 74 3d je
ffffffff814581d2
<_RNvXse_NtNtNtCshGpAVYOtgW1_4core4iter8adapters7flattenINtB5_13FlattenCompatINtNtB7_3map3MapNtNtNtBb_3str4iter5CharsNtB1v_17CharEscapeDefaultENtNtBb_4char13EscapeDefaultENtNtBb_3fmt5Debug3fmtBb_+0xf2>
The fix was proposed in [1] and initially mentioned at [2].
The second patch fixes a warning when building with clang because
there was a definition of unlikely from compiler.h in tools/include/linux,
which conflicted with the one in the instruction decoder selftest.
[1] https://lore.kernel.org/lkml/Y9ES4UKl%2F+DtvAVS@gmail.com/
[2] https://lore.kernel.org/lkml/320c4dba-9919-404b-8a26-a8af16be1845@app.fastm…
Thanks,
Sergio
Nathan Chancellor (1):
x86/tools: Drop duplicate unlikely() definition in insn_decoder_test.c
Sergio González Collado (1):
Kunit to check the longest symbol length
arch/x86/tools/insn_decoder_test.c | 5 +-
lib/Kconfig.debug | 9 ++++
lib/Makefile | 2 +
lib/longest_symbol_kunit.c | 82 ++++++++++++++++++++++++++++++
4 files changed, 95 insertions(+), 3 deletions(-)
create mode 100644 lib/longest_symbol_kunit.c
base-commit: 6282921b6825fef6a1243e1c80063421d41e2576
--
2.39.2
On Thu, Jun 19, 2025 at 10:28:00PM -0400, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
>
> arm64/cpuinfo: only show one cpu's info in c_show()
>
> to the 6.15-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
>
> The filename of the patch is:
> arm64-cpuinfo-only-show-one-cpu-s-info-in-c_show.patch
> and it can be found in the queue-6.15 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable(a)vger.kernel.org> know about it.
I don't think this one needs to be backported.
Will
The patch below does not apply to the 6.1-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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x b0823d5fbacb1c551d793cbfe7af24e0d1fa45ed
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062338-sliver-bacteria-7a82@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b0823d5fbacb1c551d793cbfe7af24e0d1fa45ed Mon Sep 17 00:00:00 2001
From: Kan Liang <kan.liang(a)linux.intel.com>
Date: Thu, 12 Jun 2025 07:38:18 -0700
Subject: [PATCH] perf/x86/intel: Fix crash in icl_update_topdown_event()
The perf_fuzzer found a hard-lockup crash on a RaptorLake machine:
Oops: general protection fault, maybe for address 0xffff89aeceab400: 0000
CPU: 23 UID: 0 PID: 0 Comm: swapper/23
Tainted: [W]=WARN
Hardware name: Dell Inc. Precision 9660/0VJ762
RIP: 0010:native_read_pmc+0x7/0x40
Code: cc e8 8d a9 01 00 48 89 03 5b cd cc cc cc cc 0f 1f ...
RSP: 000:fffb03100273de8 EFLAGS: 00010046
....
Call Trace:
<TASK>
icl_update_topdown_event+0x165/0x190
? ktime_get+0x38/0xd0
intel_pmu_read_event+0xf9/0x210
__perf_event_read+0xf9/0x210
CPUs 16-23 are E-core CPUs that don't support the perf metrics feature.
The icl_update_topdown_event() should not be invoked on these CPUs.
It's a regression of commit:
f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
The bug introduced by that commit is that the is_topdown_event() function
is mistakenly used to replace the is_topdown_count() call to check if the
topdown functions for the perf metrics feature should be invoked.
Fix it.
Fixes: f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
Closes: https://lore.kernel.org/lkml/352f0709-f026-cd45-e60c-60dfd97f73f3@maine.edu/
Reported-by: Vince Weaver <vincent.weaver(a)maine.edu>
Signed-off-by: Kan Liang <kan.liang(a)linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Tested-by: Vince Weaver <vincent.weaver(a)maine.edu>
Cc: stable(a)vger.kernel.org # v6.15+
Link: https://lore.kernel.org/r/20250612143818.2889040-1-kan.liang@linux.intel.com
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 741b229f0718..c2fb729c270e 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -2826,7 +2826,7 @@ static void intel_pmu_read_event(struct perf_event *event)
* If the PEBS counters snapshotting is enabled,
* the topdown event is available in PEBS records.
*/
- if (is_topdown_event(event) && !is_pebs_counter_event_group(event))
+ if (is_topdown_count(event) && !is_pebs_counter_event_group(event))
static_call(intel_pmu_update_topdown_event)(event, NULL);
else
intel_pmu_drain_pebs_buffer();
The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x b0823d5fbacb1c551d793cbfe7af24e0d1fa45ed
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062337-conceal-parole-52a4@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b0823d5fbacb1c551d793cbfe7af24e0d1fa45ed Mon Sep 17 00:00:00 2001
From: Kan Liang <kan.liang(a)linux.intel.com>
Date: Thu, 12 Jun 2025 07:38:18 -0700
Subject: [PATCH] perf/x86/intel: Fix crash in icl_update_topdown_event()
The perf_fuzzer found a hard-lockup crash on a RaptorLake machine:
Oops: general protection fault, maybe for address 0xffff89aeceab400: 0000
CPU: 23 UID: 0 PID: 0 Comm: swapper/23
Tainted: [W]=WARN
Hardware name: Dell Inc. Precision 9660/0VJ762
RIP: 0010:native_read_pmc+0x7/0x40
Code: cc e8 8d a9 01 00 48 89 03 5b cd cc cc cc cc 0f 1f ...
RSP: 000:fffb03100273de8 EFLAGS: 00010046
....
Call Trace:
<TASK>
icl_update_topdown_event+0x165/0x190
? ktime_get+0x38/0xd0
intel_pmu_read_event+0xf9/0x210
__perf_event_read+0xf9/0x210
CPUs 16-23 are E-core CPUs that don't support the perf metrics feature.
The icl_update_topdown_event() should not be invoked on these CPUs.
It's a regression of commit:
f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
The bug introduced by that commit is that the is_topdown_event() function
is mistakenly used to replace the is_topdown_count() call to check if the
topdown functions for the perf metrics feature should be invoked.
Fix it.
Fixes: f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
Closes: https://lore.kernel.org/lkml/352f0709-f026-cd45-e60c-60dfd97f73f3@maine.edu/
Reported-by: Vince Weaver <vincent.weaver(a)maine.edu>
Signed-off-by: Kan Liang <kan.liang(a)linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Tested-by: Vince Weaver <vincent.weaver(a)maine.edu>
Cc: stable(a)vger.kernel.org # v6.15+
Link: https://lore.kernel.org/r/20250612143818.2889040-1-kan.liang@linux.intel.com
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 741b229f0718..c2fb729c270e 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -2826,7 +2826,7 @@ static void intel_pmu_read_event(struct perf_event *event)
* If the PEBS counters snapshotting is enabled,
* the topdown event is available in PEBS records.
*/
- if (is_topdown_event(event) && !is_pebs_counter_event_group(event))
+ if (is_topdown_count(event) && !is_pebs_counter_event_group(event))
static_call(intel_pmu_update_topdown_event)(event, NULL);
else
intel_pmu_drain_pebs_buffer();
The patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x b0823d5fbacb1c551d793cbfe7af24e0d1fa45ed
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062336-reorder-unaware-0fd1@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b0823d5fbacb1c551d793cbfe7af24e0d1fa45ed Mon Sep 17 00:00:00 2001
From: Kan Liang <kan.liang(a)linux.intel.com>
Date: Thu, 12 Jun 2025 07:38:18 -0700
Subject: [PATCH] perf/x86/intel: Fix crash in icl_update_topdown_event()
The perf_fuzzer found a hard-lockup crash on a RaptorLake machine:
Oops: general protection fault, maybe for address 0xffff89aeceab400: 0000
CPU: 23 UID: 0 PID: 0 Comm: swapper/23
Tainted: [W]=WARN
Hardware name: Dell Inc. Precision 9660/0VJ762
RIP: 0010:native_read_pmc+0x7/0x40
Code: cc e8 8d a9 01 00 48 89 03 5b cd cc cc cc cc 0f 1f ...
RSP: 000:fffb03100273de8 EFLAGS: 00010046
....
Call Trace:
<TASK>
icl_update_topdown_event+0x165/0x190
? ktime_get+0x38/0xd0
intel_pmu_read_event+0xf9/0x210
__perf_event_read+0xf9/0x210
CPUs 16-23 are E-core CPUs that don't support the perf metrics feature.
The icl_update_topdown_event() should not be invoked on these CPUs.
It's a regression of commit:
f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
The bug introduced by that commit is that the is_topdown_event() function
is mistakenly used to replace the is_topdown_count() call to check if the
topdown functions for the perf metrics feature should be invoked.
Fix it.
Fixes: f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
Closes: https://lore.kernel.org/lkml/352f0709-f026-cd45-e60c-60dfd97f73f3@maine.edu/
Reported-by: Vince Weaver <vincent.weaver(a)maine.edu>
Signed-off-by: Kan Liang <kan.liang(a)linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Tested-by: Vince Weaver <vincent.weaver(a)maine.edu>
Cc: stable(a)vger.kernel.org # v6.15+
Link: https://lore.kernel.org/r/20250612143818.2889040-1-kan.liang@linux.intel.com
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 741b229f0718..c2fb729c270e 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -2826,7 +2826,7 @@ static void intel_pmu_read_event(struct perf_event *event)
* If the PEBS counters snapshotting is enabled,
* the topdown event is available in PEBS records.
*/
- if (is_topdown_event(event) && !is_pebs_counter_event_group(event))
+ if (is_topdown_count(event) && !is_pebs_counter_event_group(event))
static_call(intel_pmu_update_topdown_event)(event, NULL);
else
intel_pmu_drain_pebs_buffer();
From: Kairui Song <kasong(a)tencent.com>
The current swap-in code assumes that, when a swap entry in shmem
mapping is order 0, its cached folios (if present) must be order 0
too, which turns out not always correct.
The problem is shmem_split_large_entry is called before verifying the
folio will eventually be swapped in, one possible race is:
CPU1 CPU2
shmem_swapin_folio
/* swap in of order > 0 swap entry S1 */
folio = swap_cache_get_folio
/* folio = NULL */
order = xa_get_order
/* order > 0 */
folio = shmem_swap_alloc_folio
/* mTHP alloc failure, folio = NULL */
<... Interrupted ...>
shmem_swapin_folio
/* S1 is swapped in */
shmem_writeout
/* S1 is swapped out, folio cached */
shmem_split_large_entry(..., S1)
/* S1 is split, but the folio covering it has order > 0 now */
Now any following swapin of S1 will hang: `xa_get_order` returns 0,
and folio lookup will return a folio with order > 0. The
`xa_get_order(&mapping->i_pages, index) != folio_order(folio)` will
always return false causing swap-in to return -EEXIST.
And this looks fragile. So fix this up by allowing seeing a larger folio
in swap cache, and check the whole shmem mapping range covered by the
swapin have the right swap value upon inserting the folio. And drop
the redundant tree walks before the insertion.
This will actually improve the performance, as it avoided two redundant
Xarray tree walks in the hot path, and the only side effect is that in
the failure path, shmem may redundantly reallocate a few folios
causing temporary slight memory pressure.
And worth noting, it may seems the order and value check before
inserting might help reducing the lock contention, which is not true.
The swap cache layer ensures raced swapin will either see a swap cache
folio or failed to do a swapin (we have SWAP_HAS_CACHE bit even if
swap cache is bypassed), so holding the folio lock and checking the
folio flag is already good enough for avoiding the lock contention.
The chance that a folio passes the swap entry value check but the
shmem mapping slot has changed should be very low.
Cc: stable(a)vger.kernel.org
Fixes: 809bc86517cc ("mm: shmem: support large folio swap out")
Signed-off-by: Kairui Song <kasong(a)tencent.com>
Reviewed-by: Kemeng Shi <shikemeng(a)huaweicloud.com>
---
mm/shmem.c | 30 +++++++++++++++++++++---------
1 file changed, 21 insertions(+), 9 deletions(-)
diff --git a/mm/shmem.c b/mm/shmem.c
index eda35be2a8d9..4e7ef343a29b 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -884,7 +884,9 @@ static int shmem_add_to_page_cache(struct folio *folio,
pgoff_t index, void *expected, gfp_t gfp)
{
XA_STATE_ORDER(xas, &mapping->i_pages, index, folio_order(folio));
- long nr = folio_nr_pages(folio);
+ unsigned long nr = folio_nr_pages(folio);
+ swp_entry_t iter, swap;
+ void *entry;
VM_BUG_ON_FOLIO(index != round_down(index, nr), folio);
VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
@@ -896,14 +898,24 @@ static int shmem_add_to_page_cache(struct folio *folio,
gfp &= GFP_RECLAIM_MASK;
folio_throttle_swaprate(folio, gfp);
+ swap = iter = radix_to_swp_entry(expected);
do {
xas_lock_irq(&xas);
- if (expected != xas_find_conflict(&xas)) {
- xas_set_err(&xas, -EEXIST);
- goto unlock;
+ xas_for_each_conflict(&xas, entry) {
+ /*
+ * The range must either be empty, or filled with
+ * expected swap entries. Shmem swap entries are never
+ * partially freed without split of both entry and
+ * folio, so there shouldn't be any holes.
+ */
+ if (!expected || entry != swp_to_radix_entry(iter)) {
+ xas_set_err(&xas, -EEXIST);
+ goto unlock;
+ }
+ iter.val += 1 << xas_get_order(&xas);
}
- if (expected && xas_find_conflict(&xas)) {
+ if (expected && iter.val - nr != swap.val) {
xas_set_err(&xas, -EEXIST);
goto unlock;
}
@@ -2323,7 +2335,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
error = -ENOMEM;
goto failed;
}
- } else if (order != folio_order(folio)) {
+ } else if (order > folio_order(folio)) {
/*
* Swap readahead may swap in order 0 folios into swapcache
* asynchronously, while the shmem mapping can still stores
@@ -2348,15 +2360,15 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
swap = swp_entry(swp_type(swap), swp_offset(swap) + offset);
}
+ } else if (order < folio_order(folio)) {
+ swap.val = round_down(swp_type(swap), folio_order(folio));
}
alloced:
/* We have to do this with folio locked to prevent races */
folio_lock(folio);
if ((!skip_swapcache && !folio_test_swapcache(folio)) ||
- folio->swap.val != swap.val ||
- !shmem_confirm_swap(mapping, index, swap) ||
- xa_get_order(&mapping->i_pages, index) != folio_order(folio)) {
+ folio->swap.val != swap.val) {
error = -EEXIST;
goto unlock;
}
--
2.50.0
alloc_tag_top_users() attempts to lock alloc_tag_cttype->mod_lock
even when the alloc_tag_cttype is not allocated because:
1) alloc tagging is disabled because mem profiling is disabled
(!alloc_tag_cttype)
2) alloc tagging is enabled, but not yet initialized (!alloc_tag_cttype)
3) alloc tagging is enabled, but failed initialization
(!alloc_tag_cttype or IS_ERR(alloc_tag_cttype))
In all cases, alloc_tag_cttype is not allocated, and therefore
alloc_tag_top_users() should not attempt to acquire the semaphore.
This leads to a crash on memory allocation failure by attempting to
acquire a non-existent semaphore:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#3] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
CPU: 2 UID: 0 PID: 1 Comm: systemd Tainted: G D 6.16.0-rc2 #1 VOLUNTARY
Tainted: [D]=DIE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:down_read_trylock+0xaa/0x3b0
Code: d0 7c 08 84 d2 0f 85 a0 02 00 00 8b 0d df 31 dd 04 85 c9 75 29 48 b8 00 00 00 00 00 fc ff df 48 8d 6b 68 48 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 88 02 00 00 48 3b 5b 68 0f 85 53 01 00 00 65 ff
RSP: 0000:ffff8881002ce9b8 EFLAGS: 00010016
RAX: dffffc0000000000 RBX: 0000000000000070 RCX: 0000000000000000
RDX: 000000000000001b RSI: 000000000000000a RDI: 0000000000000070
RBP: 00000000000000d8 R08: 0000000000000001 R09: ffffed107dde49d1
R10: ffff8883eef24e8b R11: ffff8881002cec20 R12: 1ffff11020059d37
R13: 00000000003fff7b R14: ffff8881002cec20 R15: dffffc0000000000
FS: 00007f963f21d940(0000) GS:ffff888458ca6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f963f5edf71 CR3: 000000010672c000 CR4: 0000000000350ef0
Call Trace:
<TASK>
codetag_trylock_module_list+0xd/0x20
alloc_tag_top_users+0x369/0x4b0
__show_mem+0x1cd/0x6e0
warn_alloc+0x2b1/0x390
__alloc_frozen_pages_noprof+0x12b9/0x21a0
alloc_pages_mpol+0x135/0x3e0
alloc_slab_page+0x82/0xe0
new_slab+0x212/0x240
___slab_alloc+0x82a/0xe00
</TASK>
As David Wang points out, this issue became easier to trigger after commit
780138b12381 ("alloc_tag: check mem_profiling_support in alloc_tag_init").
Before the commit, the issue occurred only when it failed to allocate
and initialize alloc_tag_cttype or if a memory allocation fails before
alloc_tag_init() is called. After the commit, it can be easily triggered
when memory profiling is compiled but disabled at boot.
To properly determine whether alloc_tag_init() has been called and
its data structures initialized, verify that alloc_tag_cttype is a valid
pointer before acquiring the semaphore. If the variable is NULL or an error
value, it has not been properly initialized. In such a case, just skip
and do not attempt acquire the semaphore.
Reported-by: kernel test robot <oliver.sang(a)intel.com>
Closes: https://lore.kernel.org/oe-lkp/202506181351.bba867dd-lkp@intel.com
Fixes: 780138b12381 ("alloc_tag: check mem_profiling_support in alloc_tag_init")
Fixes: 1438d349d16b ("lib: add memory allocations report in show_mem()")
Cc: stable(a)vger.kernel.org
Signed-off-by: Harry Yoo <harry.yoo(a)oracle.com>
---
v1 -> v2:
- v1 fixed the bug only when MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=n.
v2 now fixes the bug even when MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=y.
I didn't expect alloc_tag_cttype to be NULL when
mem_profiling_support is true, but as David points out (Thanks David!)
if a memory allocation fails before alloc_tag_init(), it can be NULL.
So instead of indirectly checking mem_profiling_support, just directly
check if alloc_tag_cttype is allocated.
- Closes: https://lore.kernel.org/oe-lkp/202505071555.e757f1e0-lkp@intel.com
tag was removed because it was not a crash and not relevant to this
patch.
- Added Cc: stable because, if an allocation fails before
alloc_tag_init(), it can be triggered even prior-780138b12381.
I verified that the bug can be triggered in v6.12 and fixed by this
patch.
It should be quite difficult to trigger in practice, though.
Maybe I'm a bit paranoid?
lib/alloc_tag.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 66a4628185f7..d8ec4c03b7d2 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -124,7 +124,9 @@ size_t alloc_tag_top_users(struct codetag_bytes *tags, size_t count, bool can_sl
struct codetag_bytes n;
unsigned int i, nr = 0;
- if (can_sleep)
+ if (IS_ERR_OR_NULL(alloc_tag_cttype))
+ return 0;
+ else if (can_sleep)
codetag_lock_module_list(alloc_tag_cttype, true);
else if (!codetag_trylock_module_list(alloc_tag_cttype))
return 0;
--
2.43.0
The patch titled
Subject: mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd()
has been added to the -mm mm-new branch. Its filename is
mm-ptdump-take-the-memory-hotplug-lock-inside-ptdump_walk_pgd.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-new branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews. Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Anshuman Khandual <anshuman.khandual(a)arm.com>
Subject: mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd()
Date: Fri, 20 Jun 2025 10:54:27 +0530
Memory hot remove unmaps and tears down various kernel page table regions
as required. The ptdump code can race with concurrent modifications of
the kernel page tables. When leaf entries are modified concurrently, the
dump code may log stale or inconsistent information for a VA range, but
this is otherwise not harmful.
But when intermediate levels of kernel page table are freed, the dump code
will continue to use memory that has been freed and potentially
reallocated for another purpose. In such cases, the ptdump code may
dereference bogus addresses, leading to a number of potential problems.
To avoid the above mentioned race condition, platforms such as arm64,
riscv and s390 take memory hotplug lock, while dumping kernel page table
via the sysfs interface /sys/kernel/debug/kernel_page_tables.
Similar race condition exists while checking for pages that might have
been marked W+X via /sys/kernel/debug/kernel_page_tables/check_wx_pages
which in turn calls ptdump_check_wx(). Instead of solving this race
condition again, let's just move the memory hotplug lock inside generic
ptdump_check_wx() which will benefit both the scenarios.
Drop get_online_mems() and put_online_mems() combination from all existing
platform ptdump code paths.
Link: https://lkml.kernel.org/r/20250620052427.2092093-1-anshuman.khandual@arm.com
Fixes: bbd6ec605c0f ("arm64/mm: Enable memory hot remove")
Signed-off-by: Anshuman Khandual <anshuman.khandual(a)arm.com>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: Ryan Roberts <ryan.roberts(a)arm.com>
Cc: Paul Walmsley <paul.walmsley(a)sifive.com>
Cc: Palmer Dabbelt <palmer(a)dabbelt.com>
Cc: Alexander Gordeev <agordeev(a)linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer(a)linux.ibm.com>
Cc: Heiko Carstens <hca(a)linux.ibm.com>
Cc: Vasily Gorbik <gor(a)linux.ibm.com>
Cc: Christian Borntraeger <borntraeger(a)linux.ibm.com>
Cc: Sven Schnelle <svens(a)linux.ibm.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
arch/arm64/mm/ptdump_debugfs.c | 3 ---
arch/riscv/mm/ptdump.c | 3 ---
arch/s390/mm/dump_pagetables.c | 2 --
mm/ptdump.c | 2 ++
4 files changed, 2 insertions(+), 8 deletions(-)
--- a/arch/arm64/mm/ptdump_debugfs.c~mm-ptdump-take-the-memory-hotplug-lock-inside-ptdump_walk_pgd
+++ a/arch/arm64/mm/ptdump_debugfs.c
@@ -1,6 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/debugfs.h>
-#include <linux/memory_hotplug.h>
#include <linux/seq_file.h>
#include <asm/ptdump.h>
@@ -9,9 +8,7 @@ static int ptdump_show(struct seq_file *
{
struct ptdump_info *info = m->private;
- get_online_mems();
ptdump_walk(m, info);
- put_online_mems();
return 0;
}
DEFINE_SHOW_ATTRIBUTE(ptdump);
--- a/arch/riscv/mm/ptdump.c~mm-ptdump-take-the-memory-hotplug-lock-inside-ptdump_walk_pgd
+++ a/arch/riscv/mm/ptdump.c
@@ -6,7 +6,6 @@
#include <linux/efi.h>
#include <linux/init.h>
#include <linux/debugfs.h>
-#include <linux/memory_hotplug.h>
#include <linux/seq_file.h>
#include <linux/ptdump.h>
@@ -413,9 +412,7 @@ bool ptdump_check_wx(void)
static int ptdump_show(struct seq_file *m, void *v)
{
- get_online_mems();
ptdump_walk(m, m->private);
- put_online_mems();
return 0;
}
--- a/arch/s390/mm/dump_pagetables.c~mm-ptdump-take-the-memory-hotplug-lock-inside-ptdump_walk_pgd
+++ a/arch/s390/mm/dump_pagetables.c
@@ -247,11 +247,9 @@ static int ptdump_show(struct seq_file *
.marker = markers,
};
- get_online_mems();
mutex_lock(&cpa_mutex);
ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
mutex_unlock(&cpa_mutex);
- put_online_mems();
return 0;
}
DEFINE_SHOW_ATTRIBUTE(ptdump);
--- a/mm/ptdump.c~mm-ptdump-take-the-memory-hotplug-lock-inside-ptdump_walk_pgd
+++ a/mm/ptdump.c
@@ -176,6 +176,7 @@ void ptdump_walk_pgd(struct ptdump_state
{
const struct ptdump_range *range = st->range;
+ get_online_mems();
mmap_write_lock(mm);
while (range->start != range->end) {
walk_page_range_debug(mm, range->start, range->end,
@@ -183,6 +184,7 @@ void ptdump_walk_pgd(struct ptdump_state
range++;
}
mmap_write_unlock(mm);
+ put_online_mems();
/* Flush out the last page */
st->note_page_flush(st);
_
Patches currently in -mm which might be from anshuman.khandual(a)arm.com are
mm-ptdump-take-the-memory-hotplug-lock-inside-ptdump_walk_pgd.patch
The patch titled
Subject: mm,hugetlb: change mechanism to detect a COW on private mapping
has been added to the -mm mm-new branch. Its filename is
mmhugetlb-change-mechanism-to-detect-a-cow-on-private-mapping.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-new branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews. Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Oscar Salvador <osalvador(a)suse.de>
Subject: mm,hugetlb: change mechanism to detect a COW on private mapping
Date: Fri, 20 Jun 2025 14:30:10 +0200
Patch series "Misc rework on hugetlb faulting path", v2.
This patchset aims to give some love to the hugetlb faulting path, doing
so by removing obsolete comments that are no longer true, sorting out the
folio lock, and changing the mechanism we use to determine whether we are
COWing a private mapping already.
The most important patch of the series is #1, as it fixes a deadlock that
was described in [1], where two processes were holding the same lock for
the folio in the pagecache, and then deadlocked in the mutex.
Looking up and locking the folio in the pagecache was done to check
whether that folio was the same folio we had mapped in our pagetables,
meaning that if it was different we knew that we already mapped that folio
privately, so any further CoW would be made on a private mapping, which
lead us to the question: __Was the reservation for that address
consumed?__ That is all we care about, because if it was indeed consumed
and we are the owner and we cannot allocate more folios, we need to unmap
the folio from the processes pagetables and make it exclusive for us.
We figured we do not need to look up the folio at all, and it is just
enough to check whether the folio we have mapped is anonymous, which means
we mapped it privately, so the reservation was indeed consumed.
Patch #2 sorts out folio locking in the faulting path, reducing the scope
of it ,only taking it when we are dealing with an anonymous folio and
document it. More details in the patch.
Patches #3-5 are cleanups.
hugetlb_wp() checks whether the process is trying to COW on a private
mapping in order to know whether the reservation for that address was
already consumed or not. If it was consumed and we are the ownner of the
mapping, the folio will have to be unmapped from the other processes.
Currently, that check is done by looking up the folio in the pagecache and
comparing it to the folio which is mapped in our pagetables. If it
differs, it means we already mapped it privately before, consuming a
reservation on the way. All we are interested in is whether the mapped
folio is anonymous, so we can simplify and check for that instead.
Also, we transition from a trylock to a folio_lock, since the former was
only needed when hugetlb_fault() had to lock both folios, in order to
avoid deadlock.
Link: https://lkml.kernel.org/r/20250620123014.29748-1-osalvador@suse.de
Link: https://lkml.kernel.org/r/20250620123014.29748-2-osalvador@suse.de
Link: https://lore.kernel.org/lkml/20250513093448.592150-1-gavinguo@igalia.com/ [1]
Fixes: 40549ba8f8e0 ("hugetlb: use new vma_lock for pmd sharing synchronization")
Reported-by: Gavin Guo <gavinguo(a)igalia.com>
Closes: https://lore.kernel.org/lkml/20250513093448.592150-1-gavinguo@igalia.com/
Signed-off-by: Oscar Salvador <osalvador(a)suse.de>
Suggested-by: Peter Xu <peterx(a)redhat.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Muchun Song <muchun.song(a)linux.dev>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/hugetlb.c | 70 +++++++++++--------------------------------------
1 file changed, 17 insertions(+), 53 deletions(-)
--- a/mm/hugetlb.c~mmhugetlb-change-mechanism-to-detect-a-cow-on-private-mapping
+++ a/mm/hugetlb.c
@@ -6130,8 +6130,7 @@ static void unmap_ref_private(struct mm_
* cannot race with other handlers or page migration.
* Keep the pte_same checks anyway to make transition from the mutex easier.
*/
-static vm_fault_t hugetlb_wp(struct folio *pagecache_folio,
- struct vm_fault *vmf)
+static vm_fault_t hugetlb_wp(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct mm_struct *mm = vma->vm_mm;
@@ -6193,16 +6192,17 @@ retry_avoidcopy:
PageAnonExclusive(&old_folio->page), &old_folio->page);
/*
- * If the process that created a MAP_PRIVATE mapping is about to
- * perform a COW due to a shared page count, attempt to satisfy
- * the allocation without using the existing reserves. The pagecache
- * page is used to determine if the reserve at this address was
- * consumed or not. If reserves were used, a partial faulted mapping
- * at the time of fork() could consume its reserves on COW instead
- * of the full address range.
+ * If the process that created a MAP_PRIVATE mapping is about to perform
+ * a COW due to a shared page count, attempt to satisfy the allocation
+ * without using the existing reserves.
+ * In order to determine where this is a COW on a MAP_PRIVATE mapping it
+ * is enough to check whether the old_folio is anonymous. This means that
+ * the reserve for this address was consumed. If reserves were used, a
+ * partial faulted mapping at the fime of fork() could consume its reserves
+ * on COW instead of the full address range.
*/
if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) &&
- old_folio != pagecache_folio)
+ folio_test_anon(old_folio))
cow_from_owner = true;
folio_get(old_folio);
@@ -6581,7 +6581,7 @@ static vm_fault_t hugetlb_no_page(struct
hugetlb_count_add(pages_per_huge_page(h), mm);
if ((vmf->flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
/* Optimization, do the COW without a second fault */
- ret = hugetlb_wp(folio, vmf);
+ ret = hugetlb_wp(vmf);
}
spin_unlock(vmf->ptl);
@@ -6648,11 +6648,9 @@ vm_fault_t hugetlb_fault(struct mm_struc
{
vm_fault_t ret;
u32 hash;
- struct folio *folio = NULL;
- struct folio *pagecache_folio = NULL;
+ struct folio *folio;
struct hstate *h = hstate_vma(vma);
struct address_space *mapping;
- int need_wait_lock = 0;
struct vm_fault vmf = {
.vma = vma,
.address = address & huge_page_mask(h),
@@ -6747,8 +6745,7 @@ vm_fault_t hugetlb_fault(struct mm_struc
* If we are going to COW/unshare the mapping later, we examine the
* pending reservations for this page now. This will ensure that any
* allocations necessary to record that reservation occur outside the
- * spinlock. Also lookup the pagecache page now as it is used to
- * determine if a reservation has been consumed.
+ * spinlock.
*/
if ((flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) &&
!(vma->vm_flags & VM_MAYSHARE) && !huge_pte_write(vmf.orig_pte)) {
@@ -6758,11 +6755,6 @@ vm_fault_t hugetlb_fault(struct mm_struc
}
/* Just decrements count, does not deallocate */
vma_end_reservation(h, vma, vmf.address);
-
- pagecache_folio = filemap_lock_hugetlb_folio(h, mapping,
- vmf.pgoff);
- if (IS_ERR(pagecache_folio))
- pagecache_folio = NULL;
}
vmf.ptl = huge_pte_lock(h, mm, vmf.pte);
@@ -6776,10 +6768,6 @@ vm_fault_t hugetlb_fault(struct mm_struc
(flags & FAULT_FLAG_WRITE) && !huge_pte_write(vmf.orig_pte)) {
if (!userfaultfd_wp_async(vma)) {
spin_unlock(vmf.ptl);
- if (pagecache_folio) {
- folio_unlock(pagecache_folio);
- folio_put(pagecache_folio);
- }
hugetlb_vma_unlock_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
return handle_userfault(&vmf, VM_UFFD_WP);
@@ -6791,23 +6779,14 @@ vm_fault_t hugetlb_fault(struct mm_struc
/* Fallthrough to CoW */
}
- /*
- * hugetlb_wp() requires page locks of pte_page(vmf.orig_pte) and
- * pagecache_folio, so here we need take the former one
- * when folio != pagecache_folio or !pagecache_folio.
- */
+ /* hugetlb_wp() requires page locks of pte_page(vmf.orig_pte) */
folio = page_folio(pte_page(vmf.orig_pte));
- if (folio != pagecache_folio)
- if (!folio_trylock(folio)) {
- need_wait_lock = 1;
- goto out_ptl;
- }
-
+ folio_lock(folio);
folio_get(folio);
if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) {
if (!huge_pte_write(vmf.orig_pte)) {
- ret = hugetlb_wp(pagecache_folio, &vmf);
+ ret = hugetlb_wp(&vmf);
goto out_put_page;
} else if (likely(flags & FAULT_FLAG_WRITE)) {
vmf.orig_pte = huge_pte_mkdirty(vmf.orig_pte);
@@ -6818,16 +6797,10 @@ vm_fault_t hugetlb_fault(struct mm_struc
flags & FAULT_FLAG_WRITE))
update_mmu_cache(vma, vmf.address, vmf.pte);
out_put_page:
- if (folio != pagecache_folio)
- folio_unlock(folio);
+ folio_unlock(folio);
folio_put(folio);
out_ptl:
spin_unlock(vmf.ptl);
-
- if (pagecache_folio) {
- folio_unlock(pagecache_folio);
- folio_put(pagecache_folio);
- }
out_mutex:
hugetlb_vma_unlock_read(vma);
@@ -6839,15 +6812,6 @@ out_mutex:
vma_end_read(vma);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
- /*
- * Generally it's safe to hold refcount during waiting page lock. But
- * here we just wait to defer the next page fault to avoid busy loop and
- * the page is not used after unlocked before returning from the current
- * page fault. So we are safe from accessing freed page, even if we wait
- * here without taking refcount.
- */
- if (need_wait_lock)
- folio_wait_locked(folio);
return ret;
}
_
Patches currently in -mm which might be from osalvador(a)suse.de are
mmslub-do-not-special-case-n_normal-nodes-for-slab_nodes.patch
mmmemory_hotplug-remove-status_change_nid_normal-and-update-documentation.patch
mmmemory_hotplug-implement-numa-node-notifier.patch
mmslub-use-node-notifier-instead-of-memory-notifier.patch
mmmemory-tiers-use-node-notifier-instead-of-memory-notifier.patch
driverscxl-use-node-notifier-instead-of-memory-notifier.patch
drivershmat-use-node-notifier-instead-of-memory-notifier.patch
kernelcpuset-use-node-notifier-instead-of-memory-notifier.patch
mmmempolicy-use-node-notifier-instead-of-memory-notifier.patch
mmpage_ext-derive-the-node-from-the-pfn.patch
mmmemory_hotplug-drop-status_change_nid-parameter-from-memory_notify.patch
mmhugetlb-change-mechanism-to-detect-a-cow-on-private-mapping.patch
mmhugetlb-sort-out-folio-locking-in-the-faulting-path.patch
mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean.patch
mmhugetlb-rename-anon_rmap-to-new_anon_folio-and-make-it-boolean-fix.patch
mmhugetlb-drop-obsolete-comment-about-non-present-pte-and-second-faults.patch
mmhugetlb-drop-unlikelys-from-hugetlb_fault.patch
From: Dominique Martinet <asmadeus(a)codewreck.org>
A buffer overflow vulnerability exists in the USB 9pfs transport layer
where inconsistent size validation between packet header parsing and
actual data copying allows a malicious USB host to overflow heap buffers.
The issue occurs because:
- usb9pfs_rx_header() validates only the declared size in packet header
- usb9pfs_rx_complete() uses req->actual (actual received bytes) for
memcpy
This allows an attacker to craft packets with small declared size
(bypassing validation) but large actual payload (triggering overflow
in memcpy).
Add validation in usb9pfs_rx_complete() to ensure req->actual does not
exceed the buffer capacity before copying data.
Reported-by: Yuhao Jiang <danisjiang(a)gmail.com>
Closes: https://lkml.kernel.org/r/20250616132539.63434-1-danisjiang@gmail.com
Fixes: a3be076dc174 ("net/9p/usbg: Add new usb gadget function transport")
Cc: stable(a)vger.kernel.org
Signed-off-by: Dominique Martinet <asmadeus(a)codewreck.org>
---
(still not actually tested, can't get dummy_hcd/gt to create a device
listed by p9_fwd.py/useable in qemu, I give up..)
Changes in v3:
- fix typo s/req_sizel/req_size/ -- sorry for that, module wasn't
built...
- Link to v2: https://lore.kernel.org/r/20250620-9p-usb_overflow-v2-1-026c6109c7a1@codewr…
Changes in v2:
- run through p9_client_cb() on error
- Link to v1: https://lore.kernel.org/r/20250616132539.63434-1-danisjiang@gmail.com
---
net/9p/trans_usbg.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/net/9p/trans_usbg.c b/net/9p/trans_usbg.c
index 6b694f117aef296a66419fed5252305e7a1d0936..468f7e8f0277b9ae5f1bb3c94c649fca97d28857 100644
--- a/net/9p/trans_usbg.c
+++ b/net/9p/trans_usbg.c
@@ -231,6 +231,8 @@ static void usb9pfs_rx_complete(struct usb_ep *ep, struct usb_request *req)
struct f_usb9pfs *usb9pfs = ep->driver_data;
struct usb_composite_dev *cdev = usb9pfs->function.config->cdev;
struct p9_req_t *p9_rx_req;
+ unsigned int req_size = req->actual;
+ int status = REQ_STATUS_RCVD;
if (req->status) {
dev_err(&cdev->gadget->dev, "%s usb9pfs complete --> %d, %d/%d\n",
@@ -242,11 +244,19 @@ static void usb9pfs_rx_complete(struct usb_ep *ep, struct usb_request *req)
if (!p9_rx_req)
return;
- memcpy(p9_rx_req->rc.sdata, req->buf, req->actual);
+ if (req_size > p9_rx_req->rc.capacity) {
+ dev_err(&cdev->gadget->dev,
+ "%s received data size %u exceeds buffer capacity %zu\n",
+ ep->name, req_size, p9_rx_req->rc.capacity);
+ req_size = 0;
+ status = REQ_STATUS_ERROR;
+ }
- p9_rx_req->rc.size = req->actual;
+ memcpy(p9_rx_req->rc.sdata, req->buf, req_size);
- p9_client_cb(usb9pfs->client, p9_rx_req, REQ_STATUS_RCVD);
+ p9_rx_req->rc.size = req_size;
+
+ p9_client_cb(usb9pfs->client, p9_rx_req, status);
p9_req_put(usb9pfs->client, p9_rx_req);
complete(&usb9pfs->received);
---
base-commit: 74b4cc9b8780bfe8a3992c9ac0033bf22ac01f19
change-id: 20250620-9p-usb_overflow-25bfc5e9bef3
Best regards,
--
Dominique Martinet <asmadeus(a)codewreck.org>
From: Dominique Martinet <asmadeus(a)codewreck.org>
A buffer overflow vulnerability exists in the USB 9pfs transport layer
where inconsistent size validation between packet header parsing and
actual data copying allows a malicious USB host to overflow heap buffers.
The issue occurs because:
- usb9pfs_rx_header() validates only the declared size in packet header
- usb9pfs_rx_complete() uses req->actual (actual received bytes) for
memcpy
This allows an attacker to craft packets with small declared size
(bypassing validation) but large actual payload (triggering overflow
in memcpy).
Add validation in usb9pfs_rx_complete() to ensure req->actual does not
exceed the buffer capacity before copying data.
Reported-by: Yuhao Jiang <danisjiang(a)gmail.com>
Closes: https://lkml.kernel.org/r/20250616132539.63434-1-danisjiang@gmail.com
Fixes: a3be076dc174 ("net/9p/usbg: Add new usb gadget function transport")
Cc: stable(a)vger.kernel.org
Signed-off-by: Dominique Martinet <asmadeus(a)codewreck.org>
---
Not actually tested, I'll try to find time to figure out how to run with
qemu for real this time...
Changes in v2:
- run through p9_client_cb() on error
- Link to v1: https://lore.kernel.org/r/20250616132539.63434-1-danisjiang@gmail.com
---
net/9p/trans_usbg.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/net/9p/trans_usbg.c b/net/9p/trans_usbg.c
index 6b694f117aef296a66419fed5252305e7a1d0936..43078e0d4ca3f4063660f659d28452c81bef10b4 100644
--- a/net/9p/trans_usbg.c
+++ b/net/9p/trans_usbg.c
@@ -231,6 +231,8 @@ static void usb9pfs_rx_complete(struct usb_ep *ep, struct usb_request *req)
struct f_usb9pfs *usb9pfs = ep->driver_data;
struct usb_composite_dev *cdev = usb9pfs->function.config->cdev;
struct p9_req_t *p9_rx_req;
+ unsigned int req_size = req->actual;
+ int status = REQ_STATUS_RCVD;
if (req->status) {
dev_err(&cdev->gadget->dev, "%s usb9pfs complete --> %d, %d/%d\n",
@@ -242,11 +244,19 @@ static void usb9pfs_rx_complete(struct usb_ep *ep, struct usb_request *req)
if (!p9_rx_req)
return;
- memcpy(p9_rx_req->rc.sdata, req->buf, req->actual);
+ if (req_size > p9_rx_req->rc.capacity) {
+ dev_err(&cdev->gadget->dev,
+ "%s received data size %u exceeds buffer capacity %zu\n",
+ ep->name, req_size, p9_rx_req->rc.capacity);
+ req_size = 0;
+ status = REQ_STATUS_ERROR;
+ }
- p9_rx_req->rc.size = req->actual;
+ memcpy(p9_rx_req->rc.sdata, req->buf, req_size);
- p9_client_cb(usb9pfs->client, p9_rx_req, REQ_STATUS_RCVD);
+ p9_rx_req->rc.size = req_sizel;
+
+ p9_client_cb(usb9pfs->client, p9_rx_req, status);
p9_req_put(usb9pfs->client, p9_rx_req);
complete(&usb9pfs->received);
---
base-commit: 74b4cc9b8780bfe8a3992c9ac0033bf22ac01f19
change-id: 20250620-9p-usb_overflow-25bfc5e9bef3
Best regards,
--
Dominique Martinet <asmadeus(a)codewreck.org>
The patch titled
Subject: kallsyms: fix build without execinfo
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
kallsyms-fix-build-without-execinfo.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Achill Gilgenast <fossdd(a)pwned.life>
Subject: kallsyms: fix build without execinfo
Date: Sun, 22 Jun 2025 03:45:49 +0200
Some libc's like musl libc don't provide execinfo.h since it's not part of
POSIX. In order to fix compilation on musl, only include execinfo.h if
available (HAVE_BACKTRACE_SUPPORT)
This was discovered with c104c16073b7 ("Kunit to check the longest symbol
length") which starts to include linux/kallsyms.h with Alpine Linux'
configs.
Link: https://lkml.kernel.org/r/20250622014608.448718-1-fossdd@pwned.life
Fixes: c104c16073b7 ("Kunit to check the longest symbol length")
Signed-off-by: Achill Gilgenast <fossdd(a)pwned.life>
Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
tools/include/linux/kallsyms.h | 4 ++++
1 file changed, 4 insertions(+)
--- a/tools/include/linux/kallsyms.h~kallsyms-fix-build-without-execinfo
+++ a/tools/include/linux/kallsyms.h
@@ -18,6 +18,7 @@ static inline const char *kallsyms_looku
return NULL;
}
+#ifdef HAVE_BACKTRACE_SUPPORT
#include <execinfo.h>
#include <stdlib.h>
static inline void print_ip_sym(const char *loglvl, unsigned long ip)
@@ -30,5 +31,8 @@ static inline void print_ip_sym(const ch
free(name);
}
+#else
+static inline void print_ip_sym(const char *loglvl, unsigned long ip) {}
+#endif
#endif
_
Patches currently in -mm which might be from fossdd(a)pwned.life are
kallsyms-fix-build-without-execinfo.patch
Hello,
Please consider applying the following commits for 6.12.y:
c104c16073b7 ("Kunit to check the longest symbol length")
f710202b2a45 ("x86/tools: Drop duplicate unlikely() definition in
insn_decoder_test.c")
They should apply cleanly.
Those two commits implement a kunit test to verify that a symbol with
KSYM_NAME_LEN of 512 can be read.
The first commit implements the test. This commit also includes a fix
for the test x86/insn_decoder_test. In the case a symbol exceeds the
symbol length limit, an error will happen:
arch/x86/tools/insn_decoder_test: error: malformed line 1152000:
tBb_+0xf2>
..which overflowed by 10 characters reading this line:
ffffffff81458193: 74 3d je
ffffffff814581d2
<_RNvXse_NtNtNtCshGpAVYOtgW1_4core4iter8adapters7flattenINtB5_13FlattenCompatINtNtB7_3map3MapNtNtNtBb_3str4iter5CharsNtB1v_17CharEscapeDefaultENtNtBb_4char13EscapeDefaultENtNtBb_3fmt5Debug3fmtBb_+0xf2>
The fix was proposed in [1] and initially mentioned at [2].
The second commit fixes a warning when building with clang because
there was a definition of unlikely from compiler.h in tools/include/linux,
which conflicted with the one in the instruction decoder selftest.
[1] https://lore.kernel.org/lkml/Y9ES4UKl%2F+DtvAVS@gmail.com/
[2] https://lore.kernel.org/lkml/320c4dba-9919-404b-8a26-a8af16be1845@app.fastm…
I will send something similar to 6.6.y and 6.1.y
Thanks!
Best regards,
Sergio
commit: 10685681bafc ("net_sched: sch_sfq: don't allow 1 packet limit")
fixes CVE-2024-57996 and commit: b3bf8f63e617 ("net_sched: sch_sfq: move
the limit validation") fixes CVE-2025-37752.
Patches 3 and 5 are CVE fixes for above mentioned CVEs. Patch 1,2 and 4
are pulled in as stable-deps.
Testeing performed on the patches 5.15.185 kernel with the above 5
patches: (Used latest upstream kselftests for tc-testing)
# ./tdc.py -f tc-tests/qdiscs/sfq.json
-- ns/SubPlugin.__init__
Test 7482: Create SFQ with default setting
Test c186: Create SFQ with limit setting
Test ae23: Create SFQ with perturb setting
Test a430: Create SFQ with quantum setting
Test 4539: Create SFQ with divisor setting
Test b089: Create SFQ with flows setting
Test 99a0: Create SFQ with depth setting
Test 7389: Create SFQ with headdrop setting
Test 6472: Create SFQ with redflowlimit setting
Test 8929: Show SFQ class
Test 4d6f: Check that limit of 1 is rejected
Test 7f8f: Check that a derived limit of 1 is rejected (limit 2 depth 1 flows 1)
Test 5168: Check that a derived limit of 1 is rejected (limit 2 depth 1 divisor 1)
All test results:
1..13
ok 1 7482 - Create SFQ with default setting
ok 2 c186 - Create SFQ with limit setting
ok 3 ae23 - Create SFQ with perturb setting
ok 4 a430 - Create SFQ with quantum setting
ok 5 4539 - Create SFQ with divisor setting
ok 6 b089 - Create SFQ with flows setting
ok 7 99a0 - Create SFQ with depth setting
ok 8 7389 - Create SFQ with headdrop setting
ok 9 6472 - Create SFQ with redflowlimit setting
ok 10 8929 - Show SFQ class
ok 11 4d6f - Check that limit of 1 is rejected
ok 12 7f8f - Check that a derived limit of 1 is rejected (limit 2 depth 1 flows 1)
ok 13 5168 - Check that a derived limit of 1 is rejected (limit 2 depth 1 divisor 1)
# uname -a
Linux hamogala-vm-6 5.15.185+ #1 SMP Fri Jun 13 18:34:53 GMT 2025 x86_64 x86_64 x86_64 GNU/Linux
I will try to send similar backports to kernels older than 5.15.y as
well.
Thanks,
Harshit
Eric Dumazet (2):
net_sched: sch_sfq: annotate data-races around q->perturb_period
net_sched: sch_sfq: handle bigger packets
Octavian Purdila (3):
net_sched: sch_sfq: don't allow 1 packet limit
net_sched: sch_sfq: use a temporary work area for validating
configuration
net_sched: sch_sfq: move the limit validation
net/sched/sch_sfq.c | 112 ++++++++++++++++++++++++++++----------------
1 file changed, 71 insertions(+), 41 deletions(-)
--
2.47.1
The patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x f4c7baa0699b69edb6887a992283b389761e0e81
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062239-playful-huff-6d2b@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f4c7baa0699b69edb6887a992283b389761e0e81 Mon Sep 17 00:00:00 2001
From: Haoxiang Li <haoxiang_li2024(a)163.com>
Date: Fri, 16 May 2025 15:16:54 +0300
Subject: [PATCH] drm/i915/display: Add check for alloc_ordered_workqueue() and
alloc_workqueue()
Add check for the return value of alloc_ordered_workqueue()
and alloc_workqueue(). Furthermore, if some allocations fail,
cleanup works are added to avoid potential memory leak problem.
Fixes: 40053823baad ("drm/i915/display: move modeset probe/remove functions to intel_display_driver.c")
Cc: stable(a)vger.kernel.org
Signed-off-by: Haoxiang Li <haoxiang_li2024(a)163.com>
Reviewed-by: Matthew Auld <matthew.auld(a)intel.com>
Link: https://lore.kernel.org/r/20d3d096c6a4907636f8a1389b3b4dd753ca356e.17473976…
Signed-off-by: Jani Nikula <jani.nikula(a)intel.com>
(cherry picked from commit dcab7a228f4ea9cda3f5b0a1f0679e046d23d7f7)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen(a)linux.intel.com>
diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c b/drivers/gpu/drm/i915/display/intel_display_driver.c
index 5c74ab5fd1aa..411fe7b918a7 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.c
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.c
@@ -244,31 +244,45 @@ int intel_display_driver_probe_noirq(struct intel_display *display)
intel_dmc_init(display);
display->wq.modeset = alloc_ordered_workqueue("i915_modeset", 0);
+ if (!display->wq.modeset) {
+ ret = -ENOMEM;
+ goto cleanup_vga_client_pw_domain_dmc;
+ }
+
display->wq.flip = alloc_workqueue("i915_flip", WQ_HIGHPRI |
WQ_UNBOUND, WQ_UNBOUND_MAX_ACTIVE);
+ if (!display->wq.flip) {
+ ret = -ENOMEM;
+ goto cleanup_wq_modeset;
+ }
+
display->wq.cleanup = alloc_workqueue("i915_cleanup", WQ_HIGHPRI, 0);
+ if (!display->wq.cleanup) {
+ ret = -ENOMEM;
+ goto cleanup_wq_flip;
+ }
intel_mode_config_init(display);
ret = intel_cdclk_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_color_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_dbuf_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_bw_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_pmdemand_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
intel_init_quirks(display);
@@ -276,6 +290,12 @@ int intel_display_driver_probe_noirq(struct intel_display *display)
return 0;
+cleanup_wq_cleanup:
+ destroy_workqueue(display->wq.cleanup);
+cleanup_wq_flip:
+ destroy_workqueue(display->wq.flip);
+cleanup_wq_modeset:
+ destroy_workqueue(display->wq.modeset);
cleanup_vga_client_pw_domain_dmc:
intel_dmc_fini(display);
intel_power_domains_driver_remove(display);
The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x f4c7baa0699b69edb6887a992283b389761e0e81
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062239-erased-bonus-68e2@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f4c7baa0699b69edb6887a992283b389761e0e81 Mon Sep 17 00:00:00 2001
From: Haoxiang Li <haoxiang_li2024(a)163.com>
Date: Fri, 16 May 2025 15:16:54 +0300
Subject: [PATCH] drm/i915/display: Add check for alloc_ordered_workqueue() and
alloc_workqueue()
Add check for the return value of alloc_ordered_workqueue()
and alloc_workqueue(). Furthermore, if some allocations fail,
cleanup works are added to avoid potential memory leak problem.
Fixes: 40053823baad ("drm/i915/display: move modeset probe/remove functions to intel_display_driver.c")
Cc: stable(a)vger.kernel.org
Signed-off-by: Haoxiang Li <haoxiang_li2024(a)163.com>
Reviewed-by: Matthew Auld <matthew.auld(a)intel.com>
Link: https://lore.kernel.org/r/20d3d096c6a4907636f8a1389b3b4dd753ca356e.17473976…
Signed-off-by: Jani Nikula <jani.nikula(a)intel.com>
(cherry picked from commit dcab7a228f4ea9cda3f5b0a1f0679e046d23d7f7)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen(a)linux.intel.com>
diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c b/drivers/gpu/drm/i915/display/intel_display_driver.c
index 5c74ab5fd1aa..411fe7b918a7 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.c
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.c
@@ -244,31 +244,45 @@ int intel_display_driver_probe_noirq(struct intel_display *display)
intel_dmc_init(display);
display->wq.modeset = alloc_ordered_workqueue("i915_modeset", 0);
+ if (!display->wq.modeset) {
+ ret = -ENOMEM;
+ goto cleanup_vga_client_pw_domain_dmc;
+ }
+
display->wq.flip = alloc_workqueue("i915_flip", WQ_HIGHPRI |
WQ_UNBOUND, WQ_UNBOUND_MAX_ACTIVE);
+ if (!display->wq.flip) {
+ ret = -ENOMEM;
+ goto cleanup_wq_modeset;
+ }
+
display->wq.cleanup = alloc_workqueue("i915_cleanup", WQ_HIGHPRI, 0);
+ if (!display->wq.cleanup) {
+ ret = -ENOMEM;
+ goto cleanup_wq_flip;
+ }
intel_mode_config_init(display);
ret = intel_cdclk_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_color_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_dbuf_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_bw_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
ret = intel_pmdemand_init(display);
if (ret)
- goto cleanup_vga_client_pw_domain_dmc;
+ goto cleanup_wq_cleanup;
intel_init_quirks(display);
@@ -276,6 +290,12 @@ int intel_display_driver_probe_noirq(struct intel_display *display)
return 0;
+cleanup_wq_cleanup:
+ destroy_workqueue(display->wq.cleanup);
+cleanup_wq_flip:
+ destroy_workqueue(display->wq.flip);
+cleanup_wq_modeset:
+ destroy_workqueue(display->wq.modeset);
cleanup_vga_client_pw_domain_dmc:
intel_dmc_fini(display);
intel_power_domains_driver_remove(display);