The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 3d3c4cd5c62f24bb3cb4511b7a95df707635e00a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101349-reptile-seldom-427d@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3d3c4cd5c62f24bb3cb4511b7a95df707635e00a Mon Sep 17 00:00:00 2001
From: Oleksij Rempel <o.rempel(a)pengutronix.de>
Date: Sun, 5 Oct 2025 10:12:03 +0200
Subject: [PATCH] net: usb: asix: hold PM usage ref to avoid PM/MDIO + RTNL
deadlock
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Prevent USB runtime PM (autosuspend) for AX88772* in bind.
usbnet enables runtime PM (autosuspend) by default, so disabling it via
the usb_driver flag is ineffective. On AX88772B, autosuspend shows no
measurable power saving with current driver (no link partner, admin
up/down). The ~0.453 W -> ~0.248 W drop on v6.1 comes from phylib powering
the PHY off on admin-down, not from USB autosuspend.
The real hazard is that with runtime PM enabled, ndo_open() (under RTNL)
may synchronously trigger autoresume (usb_autopm_get_interface()) into
asix_resume() while the USB PM lock is held. Resume paths then invoke
phylink/phylib and MDIO, which also expect RTNL, leading to possible
deadlocks or PM lock vs MDIO wake issues.
To avoid this, keep the device runtime-PM active by taking a usage
reference in ax88772_bind() and dropping it in unbind(). A non-zero PM
usage count blocks runtime suspend regardless of userspace policy
(.../power/control - pm_runtime_allow/forbid), making this approach
robust against sysfs overrides.
Holding a runtime-PM usage ref does not affect system-wide suspend;
system sleep/resume callbacks continue to run as before.
Fixes: 4a2c7217cd5a ("net: usb: asix: ax88772: manage PHY PM from MAC")
Reported-by: Hubert Wiśniewski <hubert.wisniewski.25632(a)gmail.com>
Closes: https://lore.kernel.org/all/DCGHG5UJT9G3.2K1GHFZ3H87T0@gmail.com
Tested-by: Hubert Wiśniewski <hubert.wisniewski.25632(a)gmail.com>
Reported-by: Marek Szyprowski <m.szyprowski(a)samsung.com>
Closes: https://lore.kernel.org/all/b5ea8296-f981-445d-a09a-2f389d7f6fdd@samsung.com
Cc: stable(a)vger.kernel.org
Signed-off-by: Oleksij Rempel <o.rempel(a)pengutronix.de>
Link: https://patch.msgid.link/20251005081203.3067982-1-o.rempel@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni(a)redhat.com>
diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index 792ddda1ad49..85bd5d845409 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -625,6 +625,21 @@ static void ax88772_suspend(struct usbnet *dev)
asix_read_medium_status(dev, 1));
}
+/* Notes on PM callbacks and locking context:
+ *
+ * - asix_suspend()/asix_resume() are invoked for both runtime PM and
+ * system-wide suspend/resume. For struct usb_driver the ->resume()
+ * callback does not receive pm_message_t, so the resume type cannot
+ * be distinguished here.
+ *
+ * - The MAC driver must hold RTNL when calling phylink interfaces such as
+ * phylink_suspend()/resume(). Those calls will also perform MDIO I/O.
+ *
+ * - Taking RTNL and doing MDIO from a runtime-PM resume callback (while
+ * the USB PM lock is held) is fragile. Since autosuspend brings no
+ * measurable power saving here, we block it by holding a PM usage
+ * reference in ax88772_bind().
+ */
static int asix_suspend(struct usb_interface *intf, pm_message_t message)
{
struct usbnet *dev = usb_get_intfdata(intf);
@@ -919,6 +934,13 @@ static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf)
if (ret)
goto initphy_err;
+ /* Keep this interface runtime-PM active by taking a usage ref.
+ * Prevents runtime suspend while bound and avoids resume paths
+ * that could deadlock (autoresume under RTNL while USB PM lock
+ * is held, phylink/MDIO wants RTNL).
+ */
+ pm_runtime_get_noresume(&intf->dev);
+
return 0;
initphy_err:
@@ -948,6 +970,8 @@ static void ax88772_unbind(struct usbnet *dev, struct usb_interface *intf)
phylink_destroy(priv->phylink);
ax88772_mdio_unregister(priv);
asix_rx_fixup_common_free(dev->driver_priv);
+ /* Drop the PM usage ref taken in bind() */
+ pm_runtime_put(&intf->dev);
}
static void ax88178_unbind(struct usbnet *dev, struct usb_interface *intf)
@@ -1600,6 +1624,11 @@ static struct usb_driver asix_driver = {
.resume = asix_resume,
.reset_resume = asix_resume,
.disconnect = usbnet_disconnect,
+ /* usbnet enables autosuspend by default (supports_autosuspend=1).
+ * We keep runtime-PM active for AX88772* by taking a PM usage
+ * reference in ax88772_bind() (pm_runtime_get_noresume()) and
+ * dropping it in unbind(), which effectively blocks autosuspend.
+ */
.supports_autosuspend = 1,
.disable_hub_initiated_lpm = 1,
};
Reduce la rotación y retén a tu talento clave
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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 85afa9ea122dd9d4a2ead104a951d318975dcd25
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101341-gallon-ungloved-bc19@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 85afa9ea122dd9d4a2ead104a951d318975dcd25 Mon Sep 17 00:00:00 2001
From: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com>
Date: Tue, 16 Sep 2025 11:57:56 +0900
Subject: [PATCH] PCI: endpoint: pci-epf-test: Add NULL check for DMA channels
before release
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The fields dma_chan_tx and dma_chan_rx of the struct pci_epf_test can be
NULL even after EPF initialization. Then it is prudent to check that
they have non-NULL values before releasing the channels. Add the checks
in pci_epf_test_clean_dma_chan().
Without the checks, NULL pointer dereferences happen and they can lead
to a kernel panic in some cases:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050
Call trace:
dma_release_channel+0x2c/0x120 (P)
pci_epf_test_epc_deinit+0x94/0xc0 [pci_epf_test]
pci_epc_deinit_notify+0x74/0xc0
tegra_pcie_ep_pex_rst_irq+0x250/0x5d8
irq_thread_fn+0x34/0xb8
irq_thread+0x18c/0x2e8
kthread+0x14c/0x210
ret_from_fork+0x10/0x20
Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Fixes: 5ebf3fc59bd2 ("PCI: endpoint: functions/pci-epf-test: Add DMA support to transfer data")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com>
[mani: trimmed the stack trace]
Signed-off-by: Manivannan Sadhasivam <mani(a)kernel.org>
Reviewed-by: Damien Le Moal <dlemoal(a)kernel.org>
Reviewed-by: Krzysztof Wilczyński <kwilczynski(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://patch.msgid.link/20250916025756.34807-1-shinichiro.kawasaki@wdc.com
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 09e1b8b46b55..31617772ad51 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -301,15 +301,20 @@ static void pci_epf_test_clean_dma_chan(struct pci_epf_test *epf_test)
if (!epf_test->dma_supported)
return;
- dma_release_channel(epf_test->dma_chan_tx);
- if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
+ if (epf_test->dma_chan_tx) {
+ dma_release_channel(epf_test->dma_chan_tx);
+ if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
+ epf_test->dma_chan_tx = NULL;
+ epf_test->dma_chan_rx = NULL;
+ return;
+ }
epf_test->dma_chan_tx = NULL;
- epf_test->dma_chan_rx = NULL;
- return;
}
- dma_release_channel(epf_test->dma_chan_rx);
- epf_test->dma_chan_rx = NULL;
+ if (epf_test->dma_chan_rx) {
+ dma_release_channel(epf_test->dma_chan_rx);
+ epf_test->dma_chan_rx = NULL;
+ }
}
static void pci_epf_test_print_rate(struct pci_epf_test *epf_test,
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 85afa9ea122dd9d4a2ead104a951d318975dcd25
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101340-passably-rounding-59df@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 85afa9ea122dd9d4a2ead104a951d318975dcd25 Mon Sep 17 00:00:00 2001
From: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com>
Date: Tue, 16 Sep 2025 11:57:56 +0900
Subject: [PATCH] PCI: endpoint: pci-epf-test: Add NULL check for DMA channels
before release
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The fields dma_chan_tx and dma_chan_rx of the struct pci_epf_test can be
NULL even after EPF initialization. Then it is prudent to check that
they have non-NULL values before releasing the channels. Add the checks
in pci_epf_test_clean_dma_chan().
Without the checks, NULL pointer dereferences happen and they can lead
to a kernel panic in some cases:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050
Call trace:
dma_release_channel+0x2c/0x120 (P)
pci_epf_test_epc_deinit+0x94/0xc0 [pci_epf_test]
pci_epc_deinit_notify+0x74/0xc0
tegra_pcie_ep_pex_rst_irq+0x250/0x5d8
irq_thread_fn+0x34/0xb8
irq_thread+0x18c/0x2e8
kthread+0x14c/0x210
ret_from_fork+0x10/0x20
Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Fixes: 5ebf3fc59bd2 ("PCI: endpoint: functions/pci-epf-test: Add DMA support to transfer data")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com>
[mani: trimmed the stack trace]
Signed-off-by: Manivannan Sadhasivam <mani(a)kernel.org>
Reviewed-by: Damien Le Moal <dlemoal(a)kernel.org>
Reviewed-by: Krzysztof Wilczyński <kwilczynski(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://patch.msgid.link/20250916025756.34807-1-shinichiro.kawasaki@wdc.com
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 09e1b8b46b55..31617772ad51 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -301,15 +301,20 @@ static void pci_epf_test_clean_dma_chan(struct pci_epf_test *epf_test)
if (!epf_test->dma_supported)
return;
- dma_release_channel(epf_test->dma_chan_tx);
- if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
+ if (epf_test->dma_chan_tx) {
+ dma_release_channel(epf_test->dma_chan_tx);
+ if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
+ epf_test->dma_chan_tx = NULL;
+ epf_test->dma_chan_rx = NULL;
+ return;
+ }
epf_test->dma_chan_tx = NULL;
- epf_test->dma_chan_rx = NULL;
- return;
}
- dma_release_channel(epf_test->dma_chan_rx);
- epf_test->dma_chan_rx = NULL;
+ if (epf_test->dma_chan_rx) {
+ dma_release_channel(epf_test->dma_chan_rx);
+ epf_test->dma_chan_rx = NULL;
+ }
}
static void pci_epf_test_print_rate(struct pci_epf_test *epf_test,
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 85afa9ea122dd9d4a2ead104a951d318975dcd25
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101340-marbled-uneven-a896@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 85afa9ea122dd9d4a2ead104a951d318975dcd25 Mon Sep 17 00:00:00 2001
From: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com>
Date: Tue, 16 Sep 2025 11:57:56 +0900
Subject: [PATCH] PCI: endpoint: pci-epf-test: Add NULL check for DMA channels
before release
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The fields dma_chan_tx and dma_chan_rx of the struct pci_epf_test can be
NULL even after EPF initialization. Then it is prudent to check that
they have non-NULL values before releasing the channels. Add the checks
in pci_epf_test_clean_dma_chan().
Without the checks, NULL pointer dereferences happen and they can lead
to a kernel panic in some cases:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050
Call trace:
dma_release_channel+0x2c/0x120 (P)
pci_epf_test_epc_deinit+0x94/0xc0 [pci_epf_test]
pci_epc_deinit_notify+0x74/0xc0
tegra_pcie_ep_pex_rst_irq+0x250/0x5d8
irq_thread_fn+0x34/0xb8
irq_thread+0x18c/0x2e8
kthread+0x14c/0x210
ret_from_fork+0x10/0x20
Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Fixes: 5ebf3fc59bd2 ("PCI: endpoint: functions/pci-epf-test: Add DMA support to transfer data")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki(a)wdc.com>
[mani: trimmed the stack trace]
Signed-off-by: Manivannan Sadhasivam <mani(a)kernel.org>
Reviewed-by: Damien Le Moal <dlemoal(a)kernel.org>
Reviewed-by: Krzysztof Wilczyński <kwilczynski(a)kernel.org>
Cc: stable(a)vger.kernel.org
Link: https://patch.msgid.link/20250916025756.34807-1-shinichiro.kawasaki@wdc.com
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 09e1b8b46b55..31617772ad51 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -301,15 +301,20 @@ static void pci_epf_test_clean_dma_chan(struct pci_epf_test *epf_test)
if (!epf_test->dma_supported)
return;
- dma_release_channel(epf_test->dma_chan_tx);
- if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
+ if (epf_test->dma_chan_tx) {
+ dma_release_channel(epf_test->dma_chan_tx);
+ if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
+ epf_test->dma_chan_tx = NULL;
+ epf_test->dma_chan_rx = NULL;
+ return;
+ }
epf_test->dma_chan_tx = NULL;
- epf_test->dma_chan_rx = NULL;
- return;
}
- dma_release_channel(epf_test->dma_chan_rx);
- epf_test->dma_chan_rx = NULL;
+ if (epf_test->dma_chan_rx) {
+ dma_release_channel(epf_test->dma_chan_rx);
+ epf_test->dma_chan_rx = NULL;
+ }
}
static void pci_epf_test_print_rate(struct pci_epf_test *epf_test,
When fsl_edma_alloc_chan_resources() fails after clk_prepare_enable(),
the error paths only free IRQs and destroy the TCD pool, but forget to
call clk_disable_unprepare(). This causes the channel clock to remain
enabled, leaking power and resources.
Fix it by disabling the channel clock in the error unwind path.
Fixes: d8d4355861d8 ("dmaengine: fsl-edma: add i.MX8ULP edma support")
Cc: stable(a)vger.kernel.org
Suggested-by: Frank Li <Frank.Li(a)nxp.com>
Signed-off-by: Zhen Ni <zhen.ni(a)easystack.cn>
---
Changes in v2:
- Remove FSL_EDMA_DRV_HAS_CHCLK check
Changes in v3:
- Remove cleanup
Changes in v4:
- Re-send as a new thread
---
drivers/dma/fsl-edma-common.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c
index 4976d7dde080..11655dcc4d6c 100644
--- a/drivers/dma/fsl-edma-common.c
+++ b/drivers/dma/fsl-edma-common.c
@@ -852,6 +852,7 @@ int fsl_edma_alloc_chan_resources(struct dma_chan *chan)
free_irq(fsl_chan->txirq, fsl_chan);
err_txirq:
dma_pool_destroy(fsl_chan->tcd_pool);
+ clk_disable_unprepare(fsl_chan->clk);
return ret;
}
--
2.20.1
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 4d6fc29f36341d7795db1d1819b4c15fe9be7b23
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025101300-backspace-pulmonary-5620@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4d6fc29f36341d7795db1d1819b4c15fe9be7b23 Mon Sep 17 00:00:00 2001
From: Donet Tom <donettom(a)linux.ibm.com>
Date: Wed, 24 Sep 2025 00:16:59 +0530
Subject: [PATCH] mm/ksm: fix incorrect KSM counter handling in mm_struct
during fork
Patch series "mm/ksm: Fix incorrect accounting of KSM counters during
fork", v3.
The first patch in this series fixes the incorrect accounting of KSM
counters such as ksm_merging_pages, ksm_rmap_items, and the global
ksm_zero_pages during fork.
The following patch add a selftest to verify the ksm_merging_pages counter
was updated correctly during fork.
Test Results
============
Without the first patch
-----------------------
# [RUN] test_fork_ksm_merging_page_count
not ok 10 ksm_merging_page in child: 32
With the first patch
--------------------
# [RUN] test_fork_ksm_merging_page_count
ok 10 ksm_merging_pages is not inherited after fork
This patch (of 2):
Currently, the KSM-related counters in `mm_struct`, such as
`ksm_merging_pages`, `ksm_rmap_items`, and `ksm_zero_pages`, are inherited
by the child process during fork. This results in inconsistent
accounting.
When a process uses KSM, identical pages are merged and an rmap item is
created for each merged page. The `ksm_merging_pages` and
`ksm_rmap_items` counters are updated accordingly. However, after a fork,
these counters are copied to the child while the corresponding rmap items
are not. As a result, when the child later triggers an unmerge, there are
no rmap items present in the child, so the counters remain stale, leading
to incorrect accounting.
A similar issue exists with `ksm_zero_pages`, which maintains both a
global counter and a per-process counter. During fork, the per-process
counter is inherited by the child, but the global counter is not
incremented. Since the child also references zero pages, the global
counter should be updated as well. Otherwise, during zero-page unmerge,
both the global and per-process counters are decremented, causing the
global counter to become inconsistent.
To fix this, ksm_merging_pages and ksm_rmap_items are reset to 0 during
fork, and the global ksm_zero_pages counter is updated with the
per-process ksm_zero_pages value inherited by the child. This ensures
that KSM statistics remain accurate and reflect the activity of each
process correctly.
Link: https://lkml.kernel.org/r/cover.1758648700.git.donettom@linux.ibm.com
Link: https://lkml.kernel.org/r/7b9870eb67ccc0d79593940d9dbd4a0b39b5d396.17586487…
Fixes: 7609385337a4 ("ksm: count ksm merging pages for each process")
Fixes: cb4df4cae4f2 ("ksm: count allocated ksm rmap_items for each process")
Fixes: e2942062e01d ("ksm: count all zero pages placed by KSM")
Signed-off-by: Donet Tom <donettom(a)linux.ibm.com>
Reviewed-by: Chengming Zhou <chengming.zhou(a)linux.dev>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Aboorva Devarajan <aboorvad(a)linux.ibm.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Donet Tom <donettom(a)linux.ibm.com>
Cc: "Ritesh Harjani (IBM)" <ritesh.list(a)gmail.com>
Cc: Wei Yang <richard.weiyang(a)gmail.com>
Cc: xu xin <xu.xin16(a)zte.com.cn>
Cc: <stable(a)vger.kernel.org> [6.6+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/include/linux/ksm.h b/include/linux/ksm.h
index 22e67ca7cba3..067538fc4d58 100644
--- a/include/linux/ksm.h
+++ b/include/linux/ksm.h
@@ -56,8 +56,14 @@ static inline long mm_ksm_zero_pages(struct mm_struct *mm)
static inline void ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm)
{
/* Adding mm to ksm is best effort on fork. */
- if (mm_flags_test(MMF_VM_MERGEABLE, oldmm))
+ if (mm_flags_test(MMF_VM_MERGEABLE, oldmm)) {
+ long nr_ksm_zero_pages = atomic_long_read(&mm->ksm_zero_pages);
+
+ mm->ksm_merging_pages = 0;
+ mm->ksm_rmap_items = 0;
+ atomic_long_add(nr_ksm_zero_pages, &ksm_zero_pages);
__ksm_enter(mm);
+ }
}
static inline int ksm_execve(struct mm_struct *mm)