Nilay reported that since commit daaa574aba6f ("powerpc/pseries/msi: Switch
to msi_create_parent_irq_domain()"), the NVMe driver cannot enable MSI-X
when the device's MSI-X table size is larger than the firmware's MSI quota
for the device.
This is because the commit changes how rtas_prepare_msi_irqs() is called:
- Before, it is called when interrupts are allocated at the global
interrupt domain with nvec_in being the number of allocated interrupts.
rtas_prepare_msi_irqs() can return a positive number and the allocation
will be retried.
- Now, it is called at the creation of per-device interrupt domain with
nvec_in being the number of interrupts that the device supports. If
rtas_prepare_msi_irqs() returns positive, domain creation just fails.
For Nilay's NVMe driver case, rtas_prepare_msi_irqs() returns a positive
number (the quota). This causes per-device interrupt domain creation to
fail and thus the NVMe driver cannot enable MSI-X.
Rework to make this scenario works again:
- pseries_msi_ops_prepare() only prepares as many interrupts as the quota
permit.
- pseries_irq_domain_alloc() fails if the device's quota is exceeded.
Now, if the quota is exceeded, pseries_msi_ops_prepare() will only prepare
as allowed by the quota. If device drivers attempt to allocate more
interrupts than the quota permits, pseries_irq_domain_alloc() will return
an error code and msi_handle_pci_fail() will allow device drivers a retry.
Reported-by: Nilay Shroff <nilay(a)inux.ibm.com>
Closes: https://lore.kernel.org/linuxppc-dev/6af2c4c2-97f6-4758-be33-256638ef39e5@l…
Fixes: daaa574aba6f ("powerpc/pseries/msi: Switch to msi_create_parent_irq_domain()")
Signed-off-by: Nam Cao <namcao(a)linutronix.de>
Acked-by: Nilay Shroff <nilay(a)inux.ibm.com>
Cc: stable(a)vger.kernel.org
---
arch/powerpc/platforms/pseries/msi.c | 42 ++++++++++++++++++++++++++--
1 file changed, 39 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/msi.c b/arch/powerpc/platforms/pseries/msi.c
index a82aaa786e9e..8898a968a59b 100644
--- a/arch/powerpc/platforms/pseries/msi.c
+++ b/arch/powerpc/platforms/pseries/msi.c
@@ -19,6 +19,11 @@
#include "pseries.h"
+struct pseries_msi_device {
+ unsigned int msi_quota;
+ unsigned int msi_used;
+};
+
static int query_token, change_token;
#define RTAS_QUERY_FN 0
@@ -433,8 +438,26 @@ static int pseries_msi_ops_prepare(struct irq_domain *domain, struct device *dev
struct msi_domain_info *info = domain->host_data;
struct pci_dev *pdev = to_pci_dev(dev);
int type = (info->flags & MSI_FLAG_PCI_MSIX) ? PCI_CAP_ID_MSIX : PCI_CAP_ID_MSI;
+ int ret;
+
+ struct pseries_msi_device *pseries_dev __free(kfree)
+ = kmalloc(sizeof(*pseries_dev), GFP_KERNEL);
+ if (!pseries_dev)
+ return -ENOMEM;
+
+ ret = rtas_prepare_msi_irqs(pdev, nvec, type, arg);
+ if (ret > 0) {
+ nvec = ret;
+ ret = rtas_prepare_msi_irqs(pdev, nvec, type, arg);
+ }
+ if (ret < 0)
+ return ret;
- return rtas_prepare_msi_irqs(pdev, nvec, type, arg);
+ pseries_dev->msi_quota = nvec;
+ pseries_dev->msi_used = 0;
+
+ arg->scratchpad[0].ptr = no_free_ptr(pseries_dev);
+ return 0;
}
/*
@@ -443,9 +466,13 @@ static int pseries_msi_ops_prepare(struct irq_domain *domain, struct device *dev
*/
static void pseries_msi_ops_teardown(struct irq_domain *domain, msi_alloc_info_t *arg)
{
+ struct pseries_msi_device *pseries_dev = arg->scratchpad[0].ptr;
struct pci_dev *pdev = to_pci_dev(domain->dev);
rtas_disable_msi(pdev);
+
+ WARN_ON(pseries_dev->msi_used);
+ kfree(pseries_dev);
}
static void pseries_msi_shutdown(struct irq_data *d)
@@ -546,12 +573,18 @@ static int pseries_irq_domain_alloc(struct irq_domain *domain, unsigned int virq
unsigned int nr_irqs, void *arg)
{
struct pci_controller *phb = domain->host_data;
+ struct pseries_msi_device *pseries_dev;
msi_alloc_info_t *info = arg;
struct msi_desc *desc = info->desc;
struct pci_dev *pdev = msi_desc_to_pci_dev(desc);
int hwirq;
int i, ret;
+ pseries_dev = info->scratchpad[0].ptr;
+
+ if (pseries_dev->msi_used + nr_irqs > pseries_dev->msi_quota)
+ return -ENOSPC;
+
hwirq = rtas_query_irq_number(pci_get_pdn(pdev), desc->msi_index);
if (hwirq < 0) {
dev_err(&pdev->dev, "Failed to query HW IRQ: %d\n", hwirq);
@@ -567,9 +600,10 @@ static int pseries_irq_domain_alloc(struct irq_domain *domain, unsigned int virq
goto out;
irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
- &pseries_msi_irq_chip, domain->host_data);
+ &pseries_msi_irq_chip, pseries_dev);
}
+ pseries_dev->msi_used++;
return 0;
out:
@@ -582,9 +616,11 @@ static void pseries_irq_domain_free(struct irq_domain *domain, unsigned int virq
unsigned int nr_irqs)
{
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
- struct pci_controller *phb = irq_data_get_irq_chip_data(d);
+ struct pseries_msi_device *pseries_dev = irq_data_get_irq_chip_data(d);
+ struct pci_controller *phb = domain->host_data;
pr_debug("%s bridge %pOF %d #%d\n", __func__, phb->dn, virq, nr_irqs);
+ pseries_dev->msi_used -= nr_irqs;
irq_domain_free_irqs_parent(domain, virq, nr_irqs);
}
--
2.47.3
The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 1f73b8b56cf35de29a433aee7bfff26cea98be3f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025120110-coastal-litigator-8952@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1f73b8b56cf35de29a433aee7bfff26cea98be3f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Bartosik?= <ukaszb(a)chromium.org>
Date: Wed, 19 Nov 2025 21:29:09 +0000
Subject: [PATCH] xhci: dbgtty: fix device unregister
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
When DbC is disconnected then xhci_dbc_tty_unregister_device()
is called. However if there is any user space process blocked
on write to DbC terminal device then it will never be signalled
and thus stay blocked indifinitely.
This fix adds a tty_vhangup() call in xhci_dbc_tty_unregister_device().
The tty_vhangup() wakes up any blocked writers and causes subsequent
write attempts to DbC terminal device to fail.
Cc: stable <stable(a)kernel.org>
Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver")
Signed-off-by: Łukasz Bartosik <ukaszb(a)chromium.org>
Link: https://patch.msgid.link/20251119212910.1245694-1-ukaszb@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/host/xhci-dbgtty.c b/drivers/usb/host/xhci-dbgtty.c
index b7f95565524d..57cdda4e09c8 100644
--- a/drivers/usb/host/xhci-dbgtty.c
+++ b/drivers/usb/host/xhci-dbgtty.c
@@ -550,6 +550,12 @@ static void xhci_dbc_tty_unregister_device(struct xhci_dbc *dbc)
if (!port->registered)
return;
+ /*
+ * Hang up the TTY. This wakes up any blocked
+ * writers and causes subsequent writes to fail.
+ */
+ tty_vhangup(port->port.tty);
+
tty_unregister_device(dbc_tty_driver, port->minor);
xhci_dbc_tty_exit_port(port);
port->registered = false;
Hi there,
While running performance benchmarks for the 5.15.196 LTS tags , it was
observed that several regressions across different benchmarks is being
introduced when compared to the previous 5.15.193 kernel tag. Running an
automated bisect on both of them narrowed down the culprit commit to:
- 5666bcc3c00f7 Revert "cpuidle: menu: Avoid discarding useful
information" for 5.15
Regressions on 5.15.196 include:
-9.3% : Phoronix pts/sqlite using 2 processes on OnPrem X6-2
-6.3% : Phoronix system/sqlite on OnPrem X6-2
-18% : rds-stress -M 1 (readonly rdma-mode) metrics with 1 depth & 1
thread & 1M buffer size on OnPrem X6-2
-4 -> -8% : rds-stress -M 2 (writeonly rdma-mode) metrics with 1 depth &
1 thread & 1M buffer size on OnPrem X6-2
Up to -30% : Some Netpipe metrics on OnPrem X5-2
The culprit commits' messages mention that these reverts were done due
to performance regressions introduced in Intel Jasper Lake systems but
this revert is causing issues in other systems unfortunately. I wanted
to know the maintainers' opinion on how we should proceed in order to
fix this. If we reapply it'll bring back the previous regressions on
Jasper Lake systems and if we don't revert it then it's stuck with
current regressions. If this problem has been reported before and a fix
is in the works then please let me know I shall follow developments to
that mail thread.
Thanks & Regards,
Harshvardhan
Changing the enable/disable sequence in commit c9b1150a68d9
("drm/atomic-helper: Re-order bridge chain pre-enable and post-disable")
has caused regressions on multiple platforms: R-Car, MCDE, Rockchip.
This is an alternate series to Linus' series:
https://lore.kernel.org/all/20251202-mcde-drm-regression-thirdfix-v6-0-f1bf…
This series first reverts the original commit and reverts a fix for
mediatek which is no longer needed. It then exposes helper functions
from DRM core, and finally implements the new sequence only in the tidss
driver.
There is one more fix in upstream for the original commit, commit
5d91394f2361 ("drm/exynos: fimd: Guard display clock control with
runtime PM calls"), but I have not reverted that one as it looks like a
valid patch in its own.
I added Cc stable v6.17+ to all patches, but I didn't add Fixes tags, as
I wasn't sure what should they point to. But I could perhaps add Fixes:
<original commit> to all of these.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen(a)ideasonboard.com>
---
Linus Walleij (1):
drm/atomic-helper: Export and namespace some functions
Tomi Valkeinen (3):
Revert "drm/atomic-helper: Re-order bridge chain pre-enable and post-disable"
Revert "drm/mediatek: dsi: Fix DSI host and panel bridge pre-enable order"
drm/tidss: Fix enable/disable order
drivers/gpu/drm/drm_atomic_helper.c | 122 ++++++++++++++----
drivers/gpu/drm/mediatek/mtk_dsi.c | 6 -
drivers/gpu/drm/tidss/tidss_kms.c | 30 ++++-
include/drm/drm_atomic_helper.h | 22 ++++
include/drm/drm_bridge.h | 249 ++++++++++--------------------------
5 files changed, 214 insertions(+), 215 deletions(-)
---
base-commit: 88e721ab978a86426aa08da520de77430fa7bb84
change-id: 20251205-drm-seq-fix-b4ed1f56604b
Best regards,
--
Tomi Valkeinen <tomi.valkeinen(a)ideasonboard.com>
From: Liang Jie <liangjie(a)lixiang.com>
The return value of sdio_alloc_irq() was not stored in status.
If sdio_alloc_irq() fails after rtw_drv_register_netdev() succeeds,
status remains _SUCCESS and the error path skips resource cleanup,
while rtw_drv_init() still returns success.
Store the return value of sdio_alloc_irq() in status and reuse the
existing error handling which relies on status.
Cc: stable(a)vger.kernel.org
Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver")
Reviewed-by: fanggeng <fanggeng(a)lixiang.com>
Signed-off-by: Liang Jie <liangjie(a)lixiang.com>
---
drivers/staging/rtl8723bs/os_dep/sdio_intf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/rtl8723bs/os_dep/sdio_intf.c b/drivers/staging/rtl8723bs/os_dep/sdio_intf.c
index f3caaa857c86..139ace51486d 100644
--- a/drivers/staging/rtl8723bs/os_dep/sdio_intf.c
+++ b/drivers/staging/rtl8723bs/os_dep/sdio_intf.c
@@ -377,7 +377,8 @@ static int rtw_drv_init(
if (status != _SUCCESS)
goto free_if1;
- if (sdio_alloc_irq(dvobj) != _SUCCESS)
+ status = sdio_alloc_irq(dvobj);
+ if (status != _SUCCESS)
goto free_if1;
status = _SUCCESS;
--
2.25.1
After commit a50f7456f853 ("dma-mapping: Allow use of DMA_BIT_MASK(64) in
global scope"), the DMA_BIT_MASK() macro is broken when passed non trivial
statements for the value of 'n'. This is caused by the new version missing
parenthesis around 'n' when evaluating 'n'.
One example of this breakage is the IPU6 driver now crashing due to
it getting DMA-addresses with address bit 32 set even though it has
tried to set a 32 bit DMA mask.
The IPU6 CSI2 engine has a DMA mask of either 31 or 32 bits depending
on if it is in secure mode or not and it sets this masks like this:
mmu_info->aperture_end =
(dma_addr_t)DMA_BIT_MASK(isp->secure_mode ?
IPU6_MMU_ADDR_BITS :
IPU6_MMU_ADDR_BITS_NON_SECURE);
So the 'n' argument here is "isp->secure_mode ? IPU6_MMU_ADDR_BITS :
IPU6_MMU_ADDR_BITS_NON_SECURE" which gets expanded into:
isp->secure_mode ? IPU6_MMU_ADDR_BITS : IPU6_MMU_ADDR_BITS_NON_SECURE - 1
With the -1 only being applied in the non secure case, causing
the secure mode mask to be one 1 bit too large.
Fixes: a50f7456f853 ("dma-mapping: Allow use of DMA_BIT_MASK(64) in global scope")
Cc: Sakari Ailus <sakari.ailus(a)linux.intel.com>
Cc: James Clark <james.clark(a)linaro.org>
Cc: Nathan Chancellor <nathan(a)kernel.org>
Cc: stable(a)vger.kernel.org
Signed-off-by: Hans de Goede <johannes.goede(a)oss.qualcomm.com>
---
include/linux/dma-mapping.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 2ceda49c609f..aa36a0d1d9df 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -90,7 +90,7 @@
*/
#define DMA_MAPPING_ERROR (~(dma_addr_t)0)
-#define DMA_BIT_MASK(n) GENMASK_ULL(n - 1, 0)
+#define DMA_BIT_MASK(n) GENMASK_ULL((n) - 1, 0)
struct dma_iova_state {
dma_addr_t addr;
--
2.52.0