linux/drivers
Nareshkumar Gollakoti ceb4e4f0df drm/xe/debugfs: add page-size allocation mode knob
Expose a debugfs control to override the page-size allocation mode used
for user BOs.

The interface allows switching between the default allocation policy,
forced 2M, forced 1G, and mixed allocation modes at runtime. This
provides a simple way to validate behavior and debug page-size-dependent
allocation flows.

The debugfs entry is built only when CONFIG_DRM_XE_DEBUG_PAGE_SIZE is
enabled.

v2
- update changelog to match mutex-based cur_index handling
- reset cur_index when switching to mixed mode (sashiko)

v3
- add CONFIG guard for page-size allocation debugfs support (Himal)
- create debugfs entry under CONFIG_DRM_XE_DEBUG_PAGE_SIZE

v4
- reorderd this patch with kconfig patch to ensure patch builds
- Gurding this debug knob for only discrete graphics

v5(Himal)
- Guard all page size calls with CONFIG_DRM_XE_DEBUG_PAGE_SIZE

v8(Himal)
- For read/show used READ_ONCE instead lock
- to match Reader used WRITE_ONCE under lock protection
- change modes to string format to read/writer for debugfs

v9(Himal)
- Add an OOB guard for mode in page_size_alloc_mode_show().
  This check makes the function display "unknown" if mode has been
  maliciously altered by KMD, preventing out-of-bounds access.
  Under normal operation, values set through debugfs are validated,
  so OOB values should not occur.
- simplify mode-to-string lookup using page_size_alloc_mode_names[]
- use sysfs_match_string() to parse page_size_alloc_mode writes

Signed-off-by: Nareshkumar Gollakoti <naresh.kumar.g@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patch.msgid.link/20260729121843.1255891-3-naresh.kumar.g@intel.com
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
2026-07-30 08:49:34 +05:30
..
accel Merge drm/drm-next into drm-misc-next 2026-07-08 13:00:55 +02:00
accessibility
acpi ACPI support fixes for 7.2-rc2 2026-07-03 15:13:50 -10:00
amba
android
ata Split <linux/mod_devicetable.h> in per subsystem headers 2026-07-02 20:54:26 -10:00
atm
auxdisplay Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
base regmap: Fix for v7.2 2026-06-26 10:47:26 -07:00
bcma
block Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
bluetooth Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
bus Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
cache Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
cdrom
cdx Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
char Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
clk Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
clocksource
comedi
connector
counter Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
cpufreq Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
cpuidle cpuidle: Allow exit latency to exceed target residency 2026-06-23 14:00:29 +02:00
crypto Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
cxl
dax mm.git review status for mm-hotfixes-stable..mm-stable 2026-06-19 10:14:34 -07:00
dca
devfreq Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
dibs
dio
dma Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
dma-buf Merge drm/drm-next into drm-misc-next 2026-07-08 13:00:55 +02:00
dpll Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
edac Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
eisa
extcon Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
firewire Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
firmware drm-misc-next for 7.3: 2026-07-07 09:34:04 +10:00
fpga Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
fsi Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
fwctl
gnss
gpib Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
gpio gpio fixes for v7.2-rc2 2026-07-03 05:38:12 -10:00
gpu drm/xe/debugfs: add page-size allocation mode knob 2026-07-30 08:49:34 +05:30
greybus
hid Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
hsi Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
hte Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
hv hyperv-next for v7.2-rc1 2026-06-22 08:06:13 -07:00
hwmon Split <linux/mod_devicetable.h> in per subsystem headers 2026-07-02 20:54:26 -10:00
hwspinlock
hwtracing Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
i2c Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
i3c
idle
iio Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
infiniband
input Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
interconnect Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
iommu Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
ipack
irqchip Misc irqchip driver fixes: 2026-07-05 05:29:41 -10:00
leds Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
macintosh
mailbox Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
mcb
md block-7.2-20260625 2026-06-25 09:56:47 -07:00
media Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
memory Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
memstick
message
mfd Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
misc Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
mmc Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
most
mtd Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
mux Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
net Split <linux/mod_devicetable.h> in per subsystem headers 2026-07-02 20:54:26 -10:00
nfc Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
ntb NTB updates include an EPF bug fix to prevent an invalid unmap during 2026-06-28 07:46:12 -07:00
nubus
nvdimm Updates for the 7.2 release 2026-06-18 16:27:58 -07:00
nvme block-7.2-20260625 2026-06-25 09:56:47 -07:00
nvmem Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
of Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
opp
parisc
parport
pci Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
pcmcia
peci
perf Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
phy Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
pinctrl gpio fixes for v7.2-rc2 2026-07-03 05:38:12 -10:00
platform Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
pmdomain Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
pnp Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
power Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
powercap
pps Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
ps3
ptp Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
pwm Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
rapidio mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
ras
regulator Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
remoteproc
resctrl
reset Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
rpmsg rpmsg update for v7.2 2026-06-20 23:31:15 -07:00
rtc Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
s390 s390 updates for 7.2-rc2 2026-07-04 06:28:45 -10:00
sbus
scsi mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
sh
siox Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
slimbus
soc Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
soundwire Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
spi spi: Fixes for v7.2 2026-07-05 05:24:06 -10:00
spmi Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
ssb
staging Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
target
tc
tee
thermal Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
thunderbolt USB/Thunderbolt driver changes for 7.2-rc1 2026-06-22 12:09:47 -07:00
tty Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
ufs SCSI misc on 20260621 2026-06-21 10:29:45 -07:00
uio Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
usb Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
vdpa Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
vfio vfio/pci: Expose latched module parameter policy in debugfs 2026-06-29 14:26:31 -06:00
vhost mm.git review status for mm-hotfixes-stable..mm-nonmm-stable 2026-06-21 13:20:19 -07:00
video Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
virt Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
virtio
w1 Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
watchdog Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (c files) 2026-07-03 07:38:17 +02:00
xen xenbus: reject unterminated directory replies 2026-07-01 10:01:14 +02:00
zorro
Kconfig
Makefile