Before running echo 2 > /proc/sys/vm/drop_caches the active page count was:

Active(anon):   36185016 kB

after the flush, active page count became:

Active(anon):   26430472 kB

every other meminfo metrics stayed mostly the same and the system shows that 10GB of ram was freed. These 10GB are not attributed to any of the processes. What could explain such behavior? I am running on kernel 6.8. Update: This happens when **madvise(MADV_DONTNEED)** is used to decommit RSS. If I use *MADV_FREE* instead then surpringly I do not see **hidden** kernel memory and total used memory is tightly correlated with the RSS of the main process.

After updating with pacman -Syu system fails to boot. ERROR: device '/dev/lvmSystemXXX/volRootXXX' not found. Skipping fsck. mount: /new_root: fsconfig() failed: /dev/lvmSystemXXX/volRootXXX: Can't lookup blockdev. ERROR: failed to mount '/dev/lvmSystemXXX/volRootXXX' on real root You are now being dropped into an emergecy shell. sh: can't access tty: job control truned off [rootfs ~]# Some background info Linux: [rootfs ~]# uname -a Linux archlinux 6.15.9-arch1-1 #1 SMP PREEMPT_DYNAMIC Sat, 02 Aug 2025... x86_64 GNU/Linux Drives [rootfs ~]# blkid /dev/sdb2:UUID="A123456789" TYPE="crypto_LUKS" PARTUUID="A987654321" /dev/sdb1: SEC_TYPE="msdos" LABEL_FATBOOT="BOOT" LABEL="BOOT" UUID="B123456789" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="B987654321" Is there a possibility to check if the kernel was updated and eventually downgrade from emergecy shell? mkinitcpio.conf file here # vim:set ft=sh # MODULES # The following modules are loaded before any boot hooks are # run. Advanced users may wish to specify all system modules # in this array. For instance: # MODULES=(usbhid xhci_hcd) MODULES=() # BINARIES # This setting includes any additional binaries a given user may # wish into the CPIO image. This is run last, so it may be used to # override the actual binaries included by a given hook # BINARIES are dependency parsed, so you may safely ignore libraries BINARIES=() # FILES # This setting is similar to BINARIES above, however, files are added # as-is and are not parsed in any way. This is useful for config files. FILES=() # HOOKS # This is the most important setting in this file. The HOOKS control the # modules and scripts added to the image, and what happens at boot time. # Order is important, and it is recommended that you do not change the # order in which HOOKS are added. Run 'mkinitcpio -H ' for # help on a given hook. # 'base' is _required_ unless you know precisely what you are doing. # 'udev' is _required_ in order to automatically load modules # 'filesystems' is _required_ unless you specify your fs modules in MODULES # Examples: ## This setup specifies all modules in the MODULES setting above. ## No RAID, lvm2, or encrypted root is needed. # HOOKS=(base) # ## This setup will autodetect all modules for your system and should ## work as a sane default # HOOKS=(base udev autodetect modconf block filesystems fsck) # ## This setup will generate a 'full' image which supports most systems. ## No autodetection is done. # HOOKS=(base udev modconf block filesystems fsck) # ## This setup assembles a mdadm array with an encrypted root file system. ## Note: See 'mkinitcpio -H mdadm_udev' for more information on RAID devices. # HOOKS=(base udev modconf keyboard keymap consolefont block mdadm_udev encrypt filesystems fsck) # ## This setup loads an lvm2 volume group. # HOOKS=(base udev modconf block lvm2 filesystems fsck) # ## This will create a systemd based initramfs which loads an encrypted root filesystem. # HOOKS=(base systemd autodetect modconf kms keyboard sd-vconsole sd-encrypt block filesystems fsck) # ## NOTE: If you have /usr on a separate partition, you MUST include the # usr and fsck hooks. HOOKS=(base udev autodetect microcode modconf kms keyboard keymap consolefont block filesystems fsck) # COMPRESSION # Use this to compress the initramfs image. By default, zstd compression # is used for Linux ≥ 5.9 and gzip compression is used for Linux Building image from preset: /etc/mkinitcpio.d/linux-lts.preset: 'default' [2025-08-05T00:26:32+0200] [ALPM-SCRIPTLET] ==> Using default configuration file: '/etc/mkinitcpio.conf' [2025-08-05T00:26:32+0200] [ALPM-SCRIPTLET] -> -k /boot/vmlinuz-linux-lts -g /boot/initramfs-linux-lts.img [2025-08-05T00:26:32+0200] [ALPM-SCRIPTLET] ==> Starting build: '6.12.41-1-lts' [2025-08-05T00:26:32+0200] [ALPM-SCRIPTLET] -> Running build hook: [base] ... [2025-08-05T00:26:33+0200] [ALPM-SCRIPTLET] -> Running build hook: [modconf] [2025-08-05T00:26:33+0200] [ALPM-SCRIPTLET] -> Running build hook: [block] [2025-08-05T00:26:33+0200] [ALPM-SCRIPTLET] -> Running build hook: [encrypt] [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/lib/udev/rules.d/13-dm-disk.rules': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/lib/udev/rules.d/95-dm-notify.rules': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/lib/udev/rules.d/11-dm-initramfs.rules': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/lib/ossl-modules/legacy.so': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] install: error writing '/tmp/mkinitcpio.evH3PB/root/hooks/encrypt': No space left on device [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] -> Running build hook: [lvm2] [2025-08-05T00:26:34+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/pdata_tools': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/lib/udev/rules.d/11-dm-lvm.rules': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/bin/dmsetup': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/usr/lib/udev/rules.d/13-dm-disk.rules': No space left on device ... [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/twofish_common.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/aegis128.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/async_tx/async_raid6_recov.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/sm4-aesni-avx-x86_64.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/curve25519-x86_64.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/cast6_generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/cast_common.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/hctr2.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/hid/hid-generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/ecrdsa_generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/cdrom/cdrom.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/crypto/intel/iaa/iaa_crypto.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/nvme/host/nvme.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/wp512.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/md/dm-raid.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/crypto/chelsio/chcr.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/scsi/virtio_scsi.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/fcrypt.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/cast5_generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/md/dm-mod.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/aegis128-aesni.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/des3_ede-x86_64.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/crc32c-intel.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/md/dm-thin-pool.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/camellia-x86_64.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/async_tx/async_pq.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/xxhash_generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/vmac.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/md/raid456.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/crypto_null.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/async_tx/async_xor.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/nvme/host/nvme-core.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/cryptd.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/sm4_generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/cmac.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/xcbc.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/blake2b_generic.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/arch/x86/crypto/sm3-avx-x86_64.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/md/dm-region-hash.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/drivers/crypto/padlock-sha.ko.zst': No space left on device [2025-08-05T00:26:35+0200] [ALPM-SCRIPTLET] cp: error writing '/tmp/mkinitcpio.evH3PB/root/lib/modules/6.12.41-1-lts/kernel/crypto/geniv.ko.zst': No space left on device ... [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/arch/x86/crypto/des3_ede-x86_64.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/crypto/seqiv.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/drivers/input/keyboard/applespi.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/fs/smb/common/cifs_arc4.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/drivers/mfd/max14577.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/drivers/vfio/vfio.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: failed to load symbols from /tmp/mkinitcpio.qT6HiW/root/lib/modules/6.15.9-arch1-1/kernel/fs/zonefs/zonefs.ko.zst: Invalid argument [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] depmod: ERROR: Could not create index 'modules.dep'. Output is truncated: No space left on device [2025-08-05T00:26:57+0200] [ALPM-SCRIPTLET] ==> Creating zstd-compressed initcpio image: '/boot/initramfs-linux-fallback.img' [2025-08-05T00:26:58+0200] [ALPM-SCRIPTLET] ==> WARNING: errors were encountered during the build. The image may not be complete. [2025-08-05T00:26:58+0200] [ALPM] running 'dbus-reload.hook'... [2025-08-05T00:26:58+0200] [ALPM] running 'detect-old-perl-modules.hook'... [2025-08-05T00:26:59+0200] [ALPM-SCRIPTLET] WARNING: '/usr/lib/perl5/5.40' contains data from at least 1 packages which will NOT be used by the installed perl interpreter. [2025-08-05T00:26:59+0200] [ALPM-SCRIPTLET] -> Run the following command to get a list of affected packages: pacman -Qqo '/usr/lib/perl5/5.40' [2025-08-05T00:26:59+0200] [ALPM] running 'fontconfig.hook'... [2025-08-05T00:26:59+0200] [ALPM] running 'fontconfig-32.hook'... [2025-08-05T00:27:00+0200] [ALPM] running 'gdk-pixbuf-query-loaders.hook'... [2025-08-05T00:27:00+0200] [ALPM] running 'ghc-register.hook'... [2025-08-05T00:27:13+0200] [ALPM] running 'glib-compile-schemas.hook'... [2025-08-05T00:27:13+0200] [ALPM] running 'gtk-update-icon-cache.hook'... [2025-08-05T00:27:14+0200] [ALPM] running 'texinfo-install.hook'... [2025-08-05T00:27:16+0200] [ALPM] running 'update-desktop-database.hook'... [2025-08-05T00:27:16+0200] [ALPM] running 'xorg-mkfontscale.hook'... [2025-08-05T00:27:18+0200] [PACMAN] Running 'pacman -S -y --config /etc/pacman.conf --' [2025-08-05T00:27:18+0200] [PACMAN] synchronizing package lists [2025-08-05T00:27:21+0200] [PACMAN] Running 'pacman -S -y --config /etc/pacman.conf --' [2025-08-05T00:27:21+0200] [PACMAN] synchronizing package lists [2025-08-05T00:27:24+0200] [PACMAN] Running 'pacman -S -y --config /etc/pacman.conf --' [2025-08-05T00:27:24+0200] [PACMAN] synchronizing package lists [2025-08-05T00:27:27+0200] [PACMAN] Running 'pacman -S -y --config /etc/pacman.conf --' [2025-08-05T00:27:27+0200] [PACMAN] synchronizing package lists [2025-08-05T00:28:00+0200] [PACMAN] Running 'pacman -S -y --config /etc/pacman.conf --' [2025-08-05T00:28:00+0200] [PACMAN] synchronizing package lists [2025-08-05T00:29:00+0200] [PACMAN] Running 'pacman -S -y --config /etc/pacman.conf --' [2025-08-05T00:29:00+0200] [PACMAN] synchronizing package lists

I'd like to use a multi-M.2 NVMe PCIe carrier card like an [Asus Hyper M.2 x16 Card v2](https://www.asus.com/Motherboard-Accessories/HYPER-M-2-X16-CARD-V2/) in an [HP Z240 tower workstation](https://web.archive.org/web/20220414145018/https://support.hp.com/us-en/document/c04887696) . Its C236 PCH and Skylake E3-1200V5 CPU support [PCIe bifurcation](https://web.archive.org/web/20170628175109/https://www.intel.com/content/www/us/en/intelligent-systems/maho-bay/core-i7-pcie-slot-bifurcation-demo.html) 1 of the x16 PCIe slot driven by the CPU. (Ref: [Intel 100 Series / C230 Series Chipset datasheet Vol 1](https://web.archive.org/web/20210304165912/https://www.intel.com/content/www/us/en/products/docs/chipsets/100-series-chipset-datasheet-vol-1.html) , p. 22; [Intel Xeon E3-1200V5 datasheet Vol 1](https://web.archive.org/web/20181030044706/https://www.intel.com/content/www/us/en/processors/xeon/xeon-e3-1200v5-vol-1-datasheet.html) , p. 24.) Configuring the CPU PCIe for bifurcated 1x8 + 2x4 mode would allow using 3 M.2 NVMe drives in the x16 slot. (The E3 CPU is incapable of 4x4 bifurcation, so one of the M.2 slots in a quad-carrier card like the aforementioned Asus must remain empty.) Unfortunately the Z240's BIOS Setup does not include options to configure PCIe bifurcation. Worse, it appears that [HP's *Sure Start*](https://web.archive.org/web/20241228141437/http://h10032.www1.hp.com/ctg/Manual/c05163901) dual BIOS [prevents BIOS modifications](https://web.archive.org/web/20211120042316/https://www.win-raid.com/t4593f36-HP-Pavillion-g-wm-AMI-Aptio-V-modding-trials.html#msg75578) which [could enable PCIe bifurcation](https://blog.donbowman.ca/2017/10/06/pci-e-bifurcation-explained/) . This [Intel video introduction to PCIe bifurcation](https://www.intel.com/content/www/us/en/intelligent-systems/maho-bay/core-i7-pcie-slot-bifurcation-demo.html) 1 states (at 02:34) that > The configuration of the CPU PCI Express bus is statically determined by the BIOS prior to initializaton. The BIOS determines the configuration by looking at the presence detect pins on the CPU, called CFG and CFG. Presumably this works even if BIOS Setup doesn't include any options to configure bifurcation. But this approach would require accessing and modifying connections to the physical CPU pads, which I'd prefer to avoid. Other BIOSes that do include options to configure bifurcation apparently override CFG and CFG. I have found no documentation as to how they do this, and would be grateful for any links you may be aware of. At this point I wonder: Is there a way to override CFG and CFG after the machine has booted to Linux? (I realize I probably won't be able to boot from one of the M.2 drives in this case, but that's not a requirement for this system.) I'd expect such a procedure may involve steps like [hot-resetting](https://unix.stackexchange.com/questions/73908/how-to-reset-cycle-power-to-a-pcie-device/474378#474378) the x16, x8 and x4 PCIe controllers and/or function-level-resetting PEG Root Ports 10, 11 & 12. (Ref: [Intel Xeon E3-1200V5 datasheet Vol 2](https://web.archive.org/web/20201020235947/https://www.intel.com/content/www/us/en/processors/xeon/xeon-e3-1200v5-vol-2-datasheet.html).) Maybe followed by [kexec](https://en.wikipedia.org/wiki/Kexec) ? Many thanks for any hints, tips or pointers you can provide! -------------- Editors note: 1 As of August 2025 the original _Configure PCI-Express\* Lanes for Simultaneous Applications_ Intel link is dead and the archived versions I found no longer play the embedded video. The 1st link has been changed to an archived version.

There are 32 cores in a system (2 cpus each 16 cores) and I want to limit a user to use only 4 cores (100% usage for that 4 cores). There are two kernel parameter for that according to the manuals: cpu.cfs_quota_us and cpu.cfs_period_us An example on the kernel.org document says: With 500ms period and 1000ms quota, the group can get 2 CPUs worth of runtime every 500ms. # echo 1000000 > cpu.cfs_quota_us /* quota = 1000ms */ # echo 500000 > cpu.cfs_period_us /* period = 500ms */ I want to know how those ms are determined? In my case, I think the quota is 32000000 and the period is 4000000. Am I right? The content of etc/cgconfig.conf is: group ansys { cpu { cpu.cfs_quota_us = 32000000; cpu.cfs_period_us = 4000000; } memory { memory.limit_in_bytes = 8000m; } } But it doesn't work! and I get an error when I run /etc.init.d.cgconfig start, I get this error: Failed to parse /etc/cgconfig.conf or /etc/cgconfig.d [FAILED]Starting cgconfig service: /sbin/cgconfigparser; error loading /etc/cgconfig.conf: Failed to remove a non-empty group

There's no wireless interface show in the network icon and none in when I type 'nmcli device' running dmesg shows

[130854.349171] mt7921e 0000:05:00.0: probe with driver mt7921e failed with error -22

However, the only version of mt7921e.ko.zst that isn't in the directory that I compiled my current kernel in has the same version as my current kernel. modinfo mt7921e.ko.zst shows:

:       /usr/lib/modules/6.16.0-273-tkg-eevdf/kernel/drivers/net/wireless/mediatek/mt76/mt7921/mt7921e.ko.zst
license:        Dual BSD/GPL
description:    MediaTek MT7921E (PCIe) wireless driver
author:         Lorenzo Bianconi 
author:         Sean Wang 
firmware:       mediatek/WIFI_MT7922_patch_mcu_1_1_hdr.bin
firmware:       mediatek/WIFI_RAM_CODE_MT7922_1.bin
firmware:       mediatek/WIFI_MT7961_patch_mcu_1_2_hdr.bin
firmware:       mediatek/WIFI_RAM_CODE_MT7961_1.bin
firmware:       mediatek/WIFI_MT7961_patch_mcu_1a_2_hdr.bin
firmware:       mediatek/WIFI_RAM_CODE_MT7961_1a.bin
srcversion:     579FF3B9B2F0D659D1EE01B
alias:          pci:v000014C3d00007920sv*sd*bc*sc*i*
alias:          pci:v000014C3d00000616sv*sd*bc*sc*i*
alias:          pci:v000014C3d00000608sv*sd*bc*sc*i*
alias:          pci:v00000B48d00007922sv*sd*bc*sc*i*
alias:          pci:v000014C3d00007922sv*sd*bc*sc*i*
alias:          pci:v000014C3d00007961sv*sd*bc*sc*i*
depends:        mt76-connac-lib,mt7921-common,mt792x-lib,mt76,rfkill
intree:         Y
name:           mt7921e
retpoline:      Y
vermagic:       6.16.0-273-tkg-eevdf SMP preempt mod_unload 
sig_id:         PKCS#7
signer:         Build time autogenerated kernel key
sig_key:        14:13:73:2F:93:AF:32:42:B8:04:91:B9:07:E5:D0:10:1A:DB:80:7C
sig_hashalgo:   sha512
signature:      30:66:02:31:00:CF:15:39:BD:88:4B:0D:21:03:28:74:FE:89:49:78:
                8A:43:A3:13:B9:70:3E:00:44:6E:5B:38:1D:74:EE:2D:C3:D0:A7:45:
                74:F6:08:87:6A:5D:C1:A7:58:A0:DE:C8:1C:02:31:00:BA:EE:70:E8:
                BE:D1:50:93:6A:5C:6C:94:28:C1:CA:2A:70:8B:29:2D:8E:E1:EE:72:
                9C:65:A3:F7:07:C1:D7:17:C0:42:BB:3B:C7:57:6B:47:33:8A:EE:5E:
                4C:C8:37:84
parm:           disable_aspm:disable PCI ASPM support (bool)

uname -a shows

mage 6.16.0-273-tkg-eevdf #1 SMP PREEMPT_DYNAMIC TKG Sat, 02 Aug 2025 14:38:19 +0000 x86_64 GNU/Linux

I'm running Endeavour OS I tried running 'modprobe mt7921e --force-modversion' but it gives the same error. All of the firmware files are there in /lib/firmware/mediatek. I tried using mt7921s and mt7921u, the don't give an error but they don't show a wireless device either. lspci -nn shows

:00.0 Network controller : MEDIATEK Corp. MT7922 802.11ax PCI Express Wireless Network Adapter [14c3:0616]

This issue also occurs if I boot from a livecd (which has a different kernel version).

I am trying to make mdadm call into a simple bash script which writes a message in the kernel log in case of a state change. The script is as follows,

# cat /tmp/test.sh
#!/bin/bash

echo "raid array status change" > /dev/kmsg

I have added the following to the mdadm config file

PROGRAM /tmp/test.sh
ARRAY /dev/md0 UUID=

But when I do the test, it says the md0 is being picked up, and the correct program option is being used, but nothing gets printed in dmesg

mdadm --monitor --test /dev/md0 -1

Note that when I manually run the script, it prints the message in kernel log. My questions 1. Does the above process of calling the program depend on the mail setting also? Because my mail config is not set. 2. Any idea what could be wrong or missing?

I am analyzing issues with unexpected increase of memory consumption in Linux. It is an embedded system with no swap. What is happening is over some period of time around 2GB of **MemFree/MemAvailable** (they change over time nearly identically) from **/proc/meminfo** is being dropped. But by analyzing just **/proc/meminfo** doesn't seem explaining "where" memory went. What I mean is while **MemFree/MemAvailable** is decreases, other fields doesn't seem increasing in a way to fully contribute to memory issue, there is increase in some of the consumptions in the fields but not in the amount of the drop. So I have several questions: 1. Is **/proc/meminfo** a sufficient source to analyze memory consumption. I mean not to exactly blame somebody but at least to see that let's say Slab,AnonPages etc. areas increased it consumption and so it dropped overall free/available memory? If it is not that should I analyse together with it for better picture 2. A bit more specific question. Are **HugeAnonPages** accounted within **AnonPages** or they are separately tracked?

## Context I'm having difficulty getting the kernel to load the necessary Bluetooth firmware for my XPS 9310. My model has the AX500 connectivity chip, which uses the QCA6390. Users of both [Ubuntu](https://github.com/NixOS/nixos-hardware/pull/207#issuecomment-727668837) and [Arch](https://wiki.archlinux.org/index.php/Dell_XPS_13_(9310)) have reported Bluetooth working with this model, however, I'm having difficulty finding the right kernel configuration necessary to get this working on NixOS. ## My Configuration I have enabled the following kernel configuration params with the following patch added to boot.kernelPatches in my nix configuration:

# Extra config required for Bluetooth.
    {
      name = "enable-qca6390-bluetooth";
      patch = null;
      extraConfig = ''
        BT_QCA m
        BT_HCIBTUSB m
        BT_HCIBTUSB_AUTOSUSPEND y
        BT_HCIUART m
        BT_HCIUART_QCA y
      '';
    }

I'm loading the related modules like so:

boot.kernelModules = [ "bluetooth" "btqca" "btusb" "hci_qca" "hci_uart" ];

It should go without saying that I have:

hardware.bluetooth.enable = true;

I also have:

hardware.enableRedistributableFirmware = true;

which, enables the [firmwareLinuxNonfree](https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/hardware/all-firmware.nix#L46) package, which in turn adds the firmware from the [linux-firmware](https://github.com/NixOS/nixpkgs/blob/a1ea95ba042964875bdb985d70934aca19ba0c6e/pkgs/os-specific/linux/firmware/firmware-linux-nonfree/default.nix#L8) repo, which in turn includes the [necessary QCA firmware](https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/qca) . ## The Problem This firmware can be observed being loaded in the dmesg output of two separate Ubuntu users [here](https://github.com/NixOS/nixos-hardware/pull/207#issuecomment-727860836) and [here](https://askubuntu.com/questions/1299154/dell-xps-13-9310-bluetooth-wont-find-anything) , both of which report working Bluetooth. However, I am unable to observe it being loaded in mine. For reference, here is the dmesg output from a user with working Bluetooth:

[ 2.349008] Bluetooth: Core ver 2.22
[ 2.349019] Bluetooth: HCI device and connection manager initialized
[ 2.349023] Bluetooth: HCI socket layer initialized
[ 2.349024] Bluetooth: L2CAP socket layer initialized
[ 2.349028] Bluetooth: SCO socket layer initialized
[ 2.394642] Bluetooth: HCI UART driver ver 2.3
[ 2.394644] Bluetooth: HCI UART protocol H4 registered
[ 2.394645] Bluetooth: HCI UART protocol BCSP registered
[ 2.394654] Bluetooth: HCI UART protocol LL registered
[ 2.394655] Bluetooth: HCI UART protocol ATH3K registered
[ 2.394660] Bluetooth: HCI UART protocol Three-wire (H5) registered
[ 2.394702] Bluetooth: HCI UART protocol Intel registered
[ 2.394734] Bluetooth: HCI UART protocol Broadcom registered
[ 2.394742] Bluetooth: HCI UART protocol QCA registered
[ 2.394743] Bluetooth: HCI UART protocol AG6XX registered
[ 2.394748] Bluetooth: HCI UART protocol Marvell registered
[ 2.416321] Bluetooth: hci0: setting up ROME/QCA6390
[ 2.420348] Bluetooth: hci0: Frame reassembly failed (-84)
[ 2.444937] Modules linked in: snd_pcm qrtr ns snd_seq_midi snd_seq_midi_event ath11k_pci(+) mhi snd_rawmidi ath11k hci_uart qmi_helpers btqca i915(+) snd_seq btrtl uvcvideo mac80211 snd_seq_device btbcm btintel snd_timer videobuf2_vmalloc dell_wmi drm_kms_helper input_leds videobuf2_memops dell_smbios videobuf2_v4l2 cec dcdbas snd efi_pstore serio_raw rc_core videobuf2_common hid_sensor_als i2c_algo_bit hid_sensor_trigger ucsi_acpi(+) cfg80211 fb_sys_fops industrialio_triggered_buffer processor_thermal_device typec_ucsi dell_wmi_descriptor kfifo_buf hid_sensor_iio_common intel_rapl_common soundcore industrialio wmi_bmof videodev mei_me libarc4 syscopyarea cros_ec_ishtp 8250_dw mc hid_multitouch sysfillrect mei cros_ec sysimgblt intel_soc_dts_iosf typec mac_hid bluetooth ecdh_generic ecc int3403_thermal int340x_thermal_zone acpi_pad intel_hid acpi_tad int3400_thermal acpi_thermal_rel sparse_keymap sch_fq_codel parport_pc ppdev drm lp parport ip_tables x_tables autofs4 hid_sensor_hub
[ 2.756645] Bluetooth: hci0: QCA Product ID :0x00000010
[ 2.756647] Bluetooth: hci0: QCA SOC Version :0x400a0200
[ 2.756647] Bluetooth: hci0: QCA ROM Version :0x00000200
[ 2.756648] Bluetooth: hci0: QCA Patch Version:0x00000d2b
[ 2.756650] Bluetooth: hci0: QCA controller version 0x02000200
[ 2.756651] Bluetooth: hci0: QCA Downloading qca/htbtfw20.tlv
[ 3.584055] Bluetooth: hci0: QCA Downloading qca/htnv20.bin
[ 3.777754] Bluetooth: hci0: QCA setup on UART is completed
[ 3.998318] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[ 3.998319] Bluetooth: BNEP filters: protocol multicast
[ 3.998321] Bluetooth: BNEP socket layer initialized
[ 14.108234] Bluetooth: RFCOMM TTY layer initialized
[ 14.108238] Bluetooth: RFCOMM socket layer initialized
[ 14.108242] Bluetooth: RFCOMM ver 1.11

And here is the output of dmesg | grep -i blue on my machine:

[    4.363188] Bluetooth: Core ver 2.22
[    4.363199] Bluetooth: HCI device and connection manager initialized
[    4.363201] Bluetooth: HCI socket layer initialized
[    4.363203] Bluetooth: L2CAP socket layer initialized
[    4.363205] Bluetooth: SCO socket layer initialized
[    4.379230] Bluetooth: HCI UART driver ver 2.3
[    4.379231] Bluetooth: HCI UART protocol H4 registered
[    4.379232] Bluetooth: HCI UART protocol BCSP registered
[    4.379238] Bluetooth: HCI UART protocol LL registered
[    4.379256] Bluetooth: HCI UART protocol Intel registered
[    4.379260] Bluetooth: HCI UART protocol QCA registered
[   20.090546] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[   20.090553] Bluetooth: BNEP socket layer initialized

As you can see, my Bluetooth setup never performs this step or any of the following hci0 steps:

[ 2.416321] Bluetooth: hci0: setting up ROME/QCA6390

Unsurprisingly, as a result, I'm unable to enable Bluetooth in my GNOME settings GUI, and bluetoothctl shows nothing:

$ bluetoothctl list

$ bluetoothctl devices
No default controller available

## Questions From my understanding, the firmware should be automatically loaded in the case that BT_QCA is enabled and the firmware exists, both of which should be happening as a result of my aforementioned nix configuration. Is this assumption correct? Am I missing a necessary step required to trigger the hci0 lines shown above? Any advice or ideas on how to progress would be greatly appreciated! ## System info

$ nix-shell -p nix-info --run "nix-info -m"
 - system: "x86_64-linux"
 - host os: Linux 5.10.2, NixOS, 21.03pre259798.84917aa00bf (Okapi)
 - multi-user?: yes
 - sandbox: yes
 - version: nix-env (Nix) 2.3.10
 - channels(root): "nixos-21.03pre259798.84917aa00bf, home-manager-20.09"
 - nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

$ lsmod | grep -i bt
btusb                  57344  0
btrtl                  24576  1 btusb
btbcm                  20480  1 btusb
btintel                28672  2 hci_uart,btusb
btqca                  20480  1 hci_uart
bluetooth             589824  13 btrtl,btqca,btintel,hci_uart,btbcm,bnep,btusb
usbcore               270336  5 xhci_hcd,usbhid,uvcvideo,btusb,xhci_pci

$ lspci
00:00.0 Host bridge: Intel Corporation 11th Gen Core Processor Host Bridge/DRAM Registers (rev 01)
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics (rev 01)
00:04.0 Signal processing controller: Intel Corporation Device 9a03 (rev 01)
00:06.0 PCI bridge: Intel Corporation 11th Gen Core Processor PCIe Controller (rev 01)
00:07.0 PCI bridge: Intel Corporation Tiger Lake-LP Thunderbolt PCI Express Root Port #0 (rev 01)
00:07.2 PCI bridge: Intel Corporation Tiger Lake-LP Thunderbolt PCI Express Root Port #2 (rev 01)
00:0a.0 Signal processing controller: Intel Corporation Device 9a0d (rev 01)
00:0d.0 USB controller: Intel Corporation Tiger Lake-LP Thunderbolt USB Controller (rev 01)
00:0d.2 USB controller: Intel Corporation Tiger Lake-LP Thunderbolt NHI #0 (rev 01)
00:0d.3 USB controller: Intel Corporation Tiger Lake-LP Thunderbolt NHI #1 (rev 01)
00:12.0 Serial controller: Intel Corporation Tiger Lake-LP Integrated Sensor Hub (rev 20)
00:14.0 USB controller: Intel Corporation Tiger Lake-LP USB 3.2 Gen 2x1 xHCI Host Controller (rev 20)
00:14.2 RAM memory: Intel Corporation Tiger Lake-LP Shared SRAM (rev 20)
00:15.0 Serial bus controller [0c80]: Intel Corporation Tiger Lake-LP Serial IO I2C Controller #0 (rev 20)
00:15.1 Serial bus controller [0c80]: Intel Corporation Tiger Lake-LP Serial IO I2C Controller #1 (rev 20)
00:16.0 Communication controller: Intel Corporation Tiger Lake-LP Management Engine Interface (rev 20)
00:19.0 Serial bus controller [0c80]: Intel Corporation Tiger Lake-LP Serial IO I2C Controller #4 (rev 20)
00:19.1 Serial bus controller [0c80]: Intel Corporation Tiger Lake-LP Serial IO I2C Controller #5 (rev 20)
00:1c.0 PCI bridge: Intel Corporation Device a0b8 (rev 20)
00:1d.0 PCI bridge: Intel Corporation Device a0b3 (rev 20)
00:1e.0 Communication controller: Intel Corporation Tiger Lake-LP Serial IO UART Controller #0 (rev 20)
00:1f.0 ISA bridge: Intel Corporation Tiger Lake-LP LPC Controller (rev 20)
00:1f.3 Multimedia audio controller: Intel Corporation Tiger Lake-LP Smart Sound Technology Audio Controller (rev 20)
00:1f.4 SMBus: Intel Corporation Tiger Lake-LP SMBus Controller (rev 20)
00:1f.5 Serial bus controller [0c80]: Intel Corporation Tiger Lake-LP SPI Controller (rev 20)
01:00.0 Non-Volatile memory controller: Toshiba Corporation Device 011a
56:00.0 Unassigned class [ff00]: Qualcomm Device 1101
57:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5260 PCI Express Card Reader (rev 01)

$ lsusb
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 003: ID 0c45:672a Microdia Integrated_Webcam_HD
Bus 003 Device 002: ID 27c6:533c Shenzhen Goodix Technology Co.,Ltd. FingerPrint
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

## Further Reference In case they help as a reference, here are the links to the default kernel configurations for [NixOS](https://github.com/NixOS/nixpkgs/blob/master/pkgs/os-specific/linux/kernel/common-config.nix) , [Debian](https://salsa.debian.org/kernel-team/linux/blob/master/debian/config/config) and [Arch](https://git.archlinux.org/svntogit/packages.git/tree/trunk/config?h=packages/linux) . Here is my WIP [PR](https://github.com/NixOS/nixos-hardware/pull/207) aimed at adding support for the XPS 9310 to NixOS that will include this work. Here is [my previous post](https://discourse.nixos.org/t/how-to-include-and-use-external-firmware-in-nixos-config-bluetooth-for-qca6390/10471/3) to the NixOS discourse forum asking for help with this issue, yet to receive a response as of writing this.

I am trying to enable KASAN in my Manjaro distribution for a project, but I have no idea how to. The documentation here (https://www.kernel.org/doc/html/v4.14/dev-tools/kasan.html) says just to CONFIG_KASAN = y but I have no idea where to do and what steps should I take before that, I haven't configured the kernel before, I am a beginner. So far I have found out that I can see what configurations are done by looking at /proc/config.gz Here it says that KASAN is not enabled, but I don't know where to go from here. Should I just do an echo CONFIG_KASAN= y, or do I have to rebuild the Kernel and such? Please help me.

I got an IBM x3850 type 8864 machine, I can successfully boot using a 2.6.32 kernel but when I try to use a 3.10 kernel or newer the kernel fails to initialize all PCI slots (I can fix this (manually), see below): pci 0000:19:00.0: BAR 14: can't assign mem (size 0x1a00000) pci 0000:19:00.0: BAR 13: can't assign io (size 0x3000) pci 0000:19:00.0: BAR 14: can't assign mem (size 0x1600000) pci 0000:19:00.0: BAR 13: can't assign io (size 0x3000) pci 0000:1a:00.0: BAR 14: can't assign mem (size 0x1600000) pci 0000:1a:00.0: BAR 13: assigned [io 0x7000-0x8fff] pci 0000:1b:02.0: BAR 14: can't assign mem (size 0xa00000) pci 0000:1b:04.0: BAR 14: can't assign mem (size 0xa00000) pci 0000:1b:02.0: BAR 13: assigned [io 0x7000-0x7fff] pci 0000:1b:04.0: BAR 13: assigned [io 0x8000-0x8fff] ... Which causes that my network card is not successfully loaded as the PCI bus is obviously not correctly instantiated. lspci yields the following: 00:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 04) 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] RV100 [Radeon 7000 / Radeon VE] 00:03.0 USB controller: NEC Corporation OHCI USB Controller (rev 43) 00:03.1 USB controller: NEC Corporation OHCI USB Controller (rev 43) 00:03.2 USB controller: NEC Corporation uPD72010x USB 2.0 Controller (rev 04) 00:0f.0 Host bridge: Broadcom CSB6 South Bridge (rev a0) 00:0f.1 IDE interface: Broadcom CSB6 RAID/IDE Controller (rev a0) 00:0f.3 ISA bridge: Broadcom GCLE-2 Host Bridge 01:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 04) 01:01.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5704 Gigabit Ethernet (rev 10) 01:01.1 Ethernet controller: Broadcom Corporation NetXtreme BCM5704 Gigabit Ethernet (rev 10) 01:02.0 RAID bus controller: Adaptec AAC-RAID (rev 02) 02:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 04) 06:00.0 Host bridge: IBM Calgary PCI-X Host Bridge (rev 04) 0a:00.0 PCI bridge: IBM CalIOC2 PCI-E Root Port (rev 01) 0f:00.0 PCI bridge: IBM CalIOC2 PCI-E Root Port (rev 01) 14:00.0 PCI bridge: IBM CalIOC2 PCI-E Root Port (rev 01) 19:00.0 PCI bridge: IBM CalIOC2 PCI-E Root Port (rev 01) 1a:00.0 PCI bridge: Integrated Device Technology, Inc. [IDT] PES12N3A PCI Express Switch (rev 0c) 1b:02.0 PCI bridge: Integrated Device Technology, Inc. [IDT] PES12N3A PCI Express Switch (rev 0c) 1b:04.0 PCI bridge: Integrated Device Technology, Inc. [IDT] PES12N3A PCI Express Switch (rev 0c) 1c:00.0 Ethernet controller: Intel Corporation 82576 Gigabit Network Connection (rev 01) 1c:00.1 Ethernet controller: Intel Corporation 82576 Gigabit Network Connection (rev 01) 1d:00.0 Ethernet controller: Intel Corporation 82576 Gigabit Network Connection (rev 01) 1d:00.1 Ethernet controller: Intel Corporation 82576 Gigabit Network Connection (rev 01) # FIX # I can actually fix it by removing the root PCI bus 19:00.0 PCI bridge: IBM CalIOC2 PCI-E Root Port (rev 01) via echo 1 > /sys/bus/pci/devices/0000\:19\:00.0/remove and a rescan afterwards: echo 1 > /sys/bus/pci/rescan which causes the following output: pci _bus 0000:1c: busn_res: [bus 1c] is released pci _bus 0000:1d: busn_res: [bus 1d] is released pci _bus 0000:1b: busn_res: [bus 1b-1d] is released pci _bus 0000:1a: busn_res: [bus 1a-1d] is released pci 0000:19:00.0: [1014:0308] type 01 class 0x060401 pci 0000:19:00.0: supports D1 D2 pci 0000:19:00.0: PME# supported from D0 D1 D2 D3hot D3cold pci 0000:1a:00.0: [111d:8018] type 01 class 0x060400 pci 0000:1a:00.0: PME# supported from D0 D3hot D3cold pci 0000:19:00.0: pci bridge to [bus 1a-1d] (subtractive decode) pci 0000:19:00.0: bridge window [mem 0xea800000-0xea9fffff 64bit pref] pci 0000:19:00.0: bridge window [mem 0xea800000-0xebcfffff] (subtractive decode) pci 0000:19:00.0: bridge window [io 0x7000-0x8fff] (subtractive decode) pci 0000:1b:02.0: [111d:8018] type 01 class 0x060400 pci 0000:1b:02.0: PME# supported from D0 D3hot D3cold pci 0000:1b:04.0: [111d:8018] type 01 class 0x060400 pci 0000:1b:04.0: PME# supported from D0 D3hot D3cold pci 0000:1a:00.0: pci bridge to [bus 1b-1d] pci 0000:1a:00.0: bridge window [io 0x7000-0x8fff] pci 0000:1a:00.0: bridge window [mem 0xea800000-0xea9fffff 64bit pref] .... pci 0000:1b:04.0: bridge window [mem 0xea900000-0xea9fffff 64bit pref] pci 0000:1b:02.0: bridge window [mem 0x00100000-0x001fffff 64bit pref] to [bus 1c] add_size 100000 pci 0000:1b:04.0: bridge window [mem 0x00100000-0x001fffff 64bit pref] to [bus 1d] add_size 100000 pci 0000:1b:02.0: res=[mem 0x00100000-0x001fffff 64bit pref] get_res_add_size add_size 100000 pci 0000:1b:04.0: res=[mem 0x00100000-0x001fffff 64bit pref] get_res_add_size add_size 100000 pci 0000:1a:00.0: bridge window [mem 0x00100000-0x002fffff 64bit pref] to [bus 1b-1d] add_size 200000 pci 0000:19:00.0: bridge window [io 0x1000-0x2fff] to [bus 1a-1d] add_size 1000 pci 0000:1a:00.0: res=[mem 0x00100000-0x002fffff 64bit pref] get_res_add_size add_size 200000 pci 0000:19:00.0: bridge window [mem 0x00100000-0x002fffff 64bit pref] to [bus 1a-1d] add_size 200000 pci 0000:19:00.0: bridge window [mem 0x00200000-0x015fffff] to [bus 1a-1d] add_size 200000 pci 0000:19:00.0: res=[mem 0x00200000-0x015fffff] get_res_add_size add_size 200000 pci 0000:19:00.0: res=[mem 0x00100000-0x002fffff 64bit pref] get_res_add_size add_size 200000 pci 0000:19:00.0: res=[io 0x1000-0x2fff] get_res_add_size add_size 1000 pci 0000:19:00.0: BAR 14: can't assign mem (size 0x1600000) pci 0000:19:00.0: BAR 15: assigned [mem 0xea800000-0xeabfffff 64bit pref] pci 0000:19:00.0: BAR 13: can't assign io (size 0x3000) pci 0000:19:00.0: BAR 14: assigned [mem 0xea800000-0xebbfffff] pci 0000:19:00.0: BAR 15: can't assign mem pref (size 0x200000) pci 0000:19:00.0: BAR 13: assigned [io 0x7000-0x8fff] pci 0000:19:00.0: BAR 14: can't assign mem (size 0x1400000) pci 0000:19:00.0: failed to add 200000 res=[mem 0xea800000-0xebbfffff] pci 0000:19:00.0: BAR 13: can't assign io (size 0x2000) pci 0000:19:00.0: failed to add 1000 res=[io 0x7000-0x8fff] pci 0000:1a:00.0: res=[mem 0x00100000-0x002fffff 64bit pref] get_res_add_size add_size 200000 pci 0000:1a:00.0: BAR 14: assigned [mem 0xea800000-0xebbfffff] pci 0000:1a:00.0: BAR 15: can't assign mem pref (size 0x400000) pci 0000:1a:00.0: BAR 13: assigned [io 0x7000-0x8fff] pci 0000:1a:00.0: BAR 14: assigned [mem 0xea800000-0xebbfffff] pci 0000:1a:00.0: BAR 15: can't assign mem pref (size 0x200000) pci 0000:1b:02.0: res=[mem 0x00100000-0x001fffff 64bit pref] get_res_add_size add_size 100000 pci 0000:1b:04.0: res=[mem 0x00100000-0x001fffff 64bit pref] get_res_add_size add_size 100000 pci 0000:1b:02.0: BAR 14: assigned [mem 0xea800000-0xeb1fffff] pci 0000:1b:04.0: BAR 14: assigned [mem 0xeb200000-0xebbfffff] pci 0000:1b:02.0: BAR 15: can't assign mem pref (size 0x200000) pci 0000:1b:04.0: BAR 15: can't assign mem pref (size 0x200000) pci 0000:1b:02.0: BAR 13: assigned [io 0x7000-0x7fff] pci 0000:1b:04.0: BAR 13: assigned [io 0x8000-0x8fff] pci 0000:1b:02.0: BAR 14: assigned [mem 0xea800000-0xeb1fffff] pci 0000:1b:04.0: BAR 14: assigned [mem 0xeb200000-0xebbfffff] pci 0000:1b:02.0: BAR 15: can't assign mem pref (size 0x100000) pci 0000:1b:04.0: BAR 15: can't assign mem pref (size 0x100000) pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: reg 190: [mem 0xea820000-0xea823fff 64bit pref] pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: reg 190: [mem 0xea820000-0xea823fff 64bit pref] pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: reg 190: [mem 0xea820000-0xea823fff 64bit pref] pci 0000:1c:00.1: reg 184: [mem 0xea840000-0xea843fff 64bit pref] pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: reg 190: [mem 0xea820000-0xea823fff 64bit pref] pci 0000:1c:00.1: reg 190: [mem 0xea860000-0xea863fff 64bit pref] pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: reg 190: [mem 0xea820000-0xea823fff 64bit pref] pci 0000:1c:00.1: reg 184: [mem 0xea840000-0xea843fff 64bit pref] pci 0000:1c:00.0: res=[mem 0xea800000-0xea7fffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1c:00.0: res=[mem 0xea820000-0xea81ffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1c:00.1: res=[mem 0xea840000-0xea83ffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1c:00.1: res=[mem 0xea860000-0xea85ffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1c:00.0: BAR 1: assigned [mem 0xea800000-0xeabfffff] pci 0000:1c:00.1: BAR 1: assigned [mem 0xeac00000-0xeaffffff] pci 0000:1c:00.0: BAR 0: assigned [mem 0xeb000000-0xeb01ffff] pci 0000:1c:00.1: BAR 0: assigned [mem 0xeb020000-0xeb03ffff] pci 0000:1c:00.0: BAR 3: assigned [mem 0xeb040000-0xeb043fff] pci 0000:1c:00.0: reg 184: [mem 0xea800000-0xea803fff 64bit pref] pci 0000:1c:00.0: BAR 7: assigned [mem 0xeb044000-0xeb063fff 64bit pref] pci 0000:1c:00.0: reg 190: [mem 0xea820000-0xea823fff 64bit pref] pci 0000:1c:00.0: BAR 10: assigned [mem 0xeb064000-0xeb083fff 64bit pref] pci 0000:1c:00.1: BAR 3: assigned [mem 0xeb084000-0xeb087fff] pci 0000:1c:00.1: reg 184: [mem 0xea840000-0xea843fff 64bit pref] pci 0000:1c:00.1: BAR 7: assigned [mem 0xeb088000-0xeb0a7fff 64bit pref] pci 0000:1c:00.1: reg 190: [mem 0xea860000-0xea863fff 64bit pref] pci 0000:1c:00.1: BAR 10: assigned [mem 0xeb0a8000-0xeb0c7fff 64bit pref] pci 0000:1c:00.0: BAR 2: assigned [io 0x7000-0x701f] pci 0000:1c:00.1: BAR 2: assigned [io 0x7020-0x703f] pci 0000:1b:02.0: pci bridge to [bus 1c] pci 0000:1b:02.0: bridge window [io 0x7000-0x7fff] pci 0000:1b:02.0: bridge window [mem 0xea800000-0xeb1fffff] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: reg 190: [mem 0xea920000-0xea923fff 64bit pref] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: reg 190: [mem 0xea920000-0xea923fff 64bit pref] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: reg 190: [mem 0xea920000-0xea923fff 64bit pref] pci 0000:1d:00.1: reg 184: [mem 0xea940000-0xea943fff 64bit pref] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: reg 190: [mem 0xea920000-0xea923fff 64bit pref] pci 0000:1d:00.1: reg 190: [mem 0xea960000-0xea963fff 64bit pref] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: reg 190: [mem 0xea920000-0xea923fff 64bit pref] pci 0000:1d:00.1: reg 184: [mem 0xea940000-0xea943fff 64bit pref] pci 0000:1d:00.0: res=[mem 0xea900000-0xea8fffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1d:00.0: res=[mem 0xea920000-0xea91ffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1d:00.1: res=[mem 0xea940000-0xea93ffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1d:00.1: res=[mem 0xea960000-0xea95ffff 64bit pref] get_res_add_size add_size 20000 pci 0000:1d:00.0: BAR 1: assigned [mem 0xeb400000-0xeb7fffff] pci 0000:1d:00.1: BAR 1: assigned [mem 0xeb800000-0xebbfffff] pci 0000:1d:00.0: BAR 0: assigned [mem 0xeb200000-0xeb21ffff] pci 0000:1d:00.1: BAR 0: assigned [mem 0xeb220000-0xeb23ffff] pci 0000:1d:00.0: BAR 3: assigned [mem 0xeb240000-0xeb243fff] pci 0000:1d:00.0: reg 184: [mem 0xea900000-0xea903fff 64bit pref] pci 0000:1d:00.0: BAR 7: assigned [mem 0xeb244000-0xeb263fff 64bit pref] pci 0000:1d:00.0: reg 190: [mem 0xea920000-0xea923fff 64bit pref] pci 0000:1d:00.0: BAR 10: assigned [mem 0xeb264000-0xeb283fff 64bit pref] pci 0000:1d:00.1: BAR 3: assigned [mem 0xeb284000-0xeb287fff] pci 0000:1d:00.1: reg 184: [mem 0xea940000-0xea943fff 64bit pref] pci 0000:1d:00.1: BAR 7: assigned [mem 0xeb288000-0xeb2a7fff 64bit pref] pci 0000:1d:00.1: reg 190: [mem 0xea960000-0xea963fff 64bit pref] pci 0000:1d:00.1: BAR 10: assigned [mem 0xeb2a8000-0xeb2c7fff 64bit pref] pci 0000:1d:00.0: BAR 2: assigned [io 0x8000-0x801f] pci 0000:1d:00.1: BAR 2: assigned [io 0x8020-0x803f] pci 0000:1b:04.0: pci bridge to [bus 1d] pci 0000:1b:04.0: bridge window [io 0x8000-0x8fff] pci 0000:1b:04.0: bridge window [mem 0xeb200000-0xebbfffff] pci 0000:1a:00.0: pci bridge to [bus 1b-1d] pci 0000:1a:00.0: bridge window [io 0x7000-0x8fff] pci 0000:1a:00.0: bridge window [mem 0xea800000-0xebbfffff] pci 0000:19:00.0: pci bridge to [bus 1a-1d] pci 0000:19:00.0: bridge window [io 0x7000-0x8fff] pci 0000:19:00.0: bridge window [mem 0xea800000-0xebbfffff] # QUESTION # Is it somehow possible to tell the kernel (e.g. via a parameter) to automatically do this? What is causing this issue in the first place? Thank you in advance! ## Update ## As the described fix fails on a 4.x system (actually starting with 3.12 I suppose), I had a look at the kernel and found that if I disable PCI ASPM (which was already disabled by ACPI (t can also be forced by pcie_aspm=off in kernel boot parameter)), the following small fix (on a 4.4.0) resolves a kernel null pointer dereference: --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -552,11 +552,12 @@ static struct pcie_link_state *alloc_pcie_link_state(struct pci_dev *pdev) void pcie_aspm_init_link_state(struct pci_dev *pdev) { struct pcie_link_state *link; - int blacklist = !!pcie_aspm_sanity_check(pdev); - + int blacklist; if (!aspm_support_enabled) return; + blacklist = !!pcie_aspm_sanity_check(pdev); + if (pdev->link_state) return; Kind of odd that a sanity check is performed if the feature itself is deactivated, the actual null pointer dereference happend in pcie_aspm_sanity_check in this line list_for_each_entry(child, &pdev->subordinate->devices, bus_list) {. Is this a kernel bug?

I seem to be having a bizarre problem installing a new custom kernel. update-initramfs fails during dpkg -i with: update-initramfs: Generating /boot/initrd.img-5.15.7-hardened1-test1 find: ‘/tmp/user/0/mkinitramfs_gHxWMQ/lib/modules/5.15.7-hardened1-test1/kernel’: No such file or directory Generating grub configuration file ... Found linux image: /boot/vmlinuz-5.15.7-hardened1-r7 Found initrd image: /boot/initrd.img-5.15.7-hardened1-r7 Found linux image: /boot/vmlinuz-5.15.7-hardened1-test1 Found initrd image: /boot/initrd.img-5.15.7-hardened1-test1 Found linux image: /boot/vmlinuz-5.10.0-10-amd64 Found initrd image: /boot/initrd.img-5.10.0-10-amd64 done The r7 kernel builds and installs perfectly fine, but the test1 installs with a find: ‘/tmp/user/0/mkinitramfs_gHxWMQ/lib/modules/5.15.7-hardened1-test1/kernel’: No such file or directory error. The only difference between the .configs is: 29c29 CONFIG_LOCALVERSION="-test1" 39c39 # CONFIG_KERNEL_GZIP is not set 45c45 CONFIG_KERNEL_ZSTD=y 787c787 CONFIG_MODULE_FORCE_UNLOAD=y 802,803c802,803 # CONFIG_MODULE_COMPRESS_XZ is not set > CONFIG_MODULE_COMPRESS_ZSTD=y I even tried a slightly newer kernel (5.15.27) and older (5.10.104) with the same results. Trying to boot into the kernel drops the boot to a initramfs prompt (without USB keyboard functionality) after failing to find the root LVM. The initrd images also have very different sizes for the minimal changes made: 9.7M initrd.img-5.15.7-hardened1-r7 (working) 9.1M initrd.img-5.15.7-hardened1-test1 (broke) Doing a diff between the two with lsinitrd produces this, suggesting that the initrd does indeed lack a huge number of modules. 346,399c346 5.15.7-hardened1-test1 Anyone seen this before? I found one results through google but a solution was never provided. I'm running Devuan Chimaera (Debian 11 base) with: initramfs-tools=0.140 & dpkg=1.20.9

### Context I bought a CM749 UGREEN Bluetooth 5.4 USB adapter for my Nixos machine. It is recognized by lsusb as ID 33fa:0010 USB2.0-BT, but is not detected by KDE/Plasma's bluetooth daemon. I dug deeper and found an Ubuntu bug report with the exact same problem and diagnosis as me. As of today, the last post links to an AskUbuntu post with a vexingly vague answer: > I patch my kernel source to cancel command hci_read_local_ext_features in the hci_init2[] and hci_init3[] in file hci_sync.c. It worked. So, I downloaded and unpacked the 6.15.7 kernel source from cdn.kernel.org , opened the corresponding file in Keta... and was lost like a lamb. Question: What does it mean to "cancel" a command in the linux kernel and how can one do so? Please, do tell me if my question is too vague or whether more information should be provided.

The problem is while booting up rasbberry pi with uboot as boot loader not able to decrypt encrypted rootfs partition with initramfs,to debug and analyse what happening want to enable uboot debug logs. When checked with current loglevel in Kconfig it show default i.e. CONFIG_LOGLEVEL=4 these are boot logs : U-Boot 2024.04 (Apr 02 2024 - 10:58:58 +0000) DRAM: 948 MiB (effective 7.9 GiB) RPI 4 Model B (0xd03114) Core: 213 devices, 16 uclasses, devicetree: board MMC: mmcnr@7e300000: 1, mmc@7e340000: 0 Loading Environment from MMC... *** Warning - bad CRC, using default environment In: serial,usbkbd Out: serial,vidconsole Err: serial,vidconsole Net: eth0: ethernet@7d580000 PCIe BRCM: link up, 5.0 Gbps x1 (SSC) starting USB... Bus xhci_pci: Register 5000420 NbrPorts 5 Starting the controller USB XHCI 1.00 scanning bus xhci_pci for devices... 2 USB Device(s) found scanning usb for storage devices... 0 Storage Device(s) found Hit any key to stop autoboot: 0 Card did not respond to voltage select! : -110 ethernet@7d580000 Waiting for PHY auto negotiation to complete......... TIMEOUT! bcmgenet: PHY startup failed: -110 ethernet@7d580000 Waiting for PHY auto negotiation to complete......... TIMEOUT! bcmgenet: PHY startup failed: -110 U-Boot> updated the common/Kconfig default to 7 still cannot see any change in the logs kconfig snippet: config LOGLEVEL int "loglevel" default 7 range 0 10 help All Messages with a loglevel smaller than the console loglevel will be compiled in. The loglevels are defined as follows: 0 - emergency 1 - alert 2 - critical 3 - error 4 - warning 5 - note 6 - info 7 - debug 8 - debug content 9 - debug hardware I/O don't know if im able to config it correctly or are there other config parameters need to configure and which are those please let me know if any one has done this before.

I have two screens with different native resolution connected to my Gentoo/systemd machine. since the VTs try to mirror the outputs, they do not use the whole size of the higher resolution screen. I never use virtual terminals on the lower resolution screen, so I'd like to have them use the whole high resolution monitor. If I disable the lower resolution screen with the video kernel command line parameter, I cannot switch it on in X11, since the kernel thinks the output is not connected. Nevertheless, on X11 I want to be able to enable the second monitor whenever I need it. Is there an option on the kernel command line, in systemd, or somewhere I can't think of at them moment, to disable the virtual terminals on one output, to have different virtual terminals on different outputs (kind of multiseat), to force the vts to use the whole size of one connected screen, or to disable an output on virtual terminals in such a way that xrandr can reenable it?

I've recently purchased an **NVIDIA RTX 5070 Ti**, but it doesn't work properly under Linux. The card works **perfectly under Windows 11**, so hardware failure can be ruled out. When the PC boots, I **can see the GRUB menu**, but once the OS starts loading, I completely **lose video output** — no console, no graphical interface, not even kernel messages (unless using serial output). ## Test Environment I started over from a **clean minimal Debian Trixie installation (no X or Wayland)** with an **NVIDIA GTX 970**, which works fine. I then performed several tests while **capturing logs via the motherboard's RS232 serial port**. Initially, I was using **Debian stable (Bookworm)**, but I upgraded to **Trixie** thinking the issue might come from an outdated kernel. Unfortunately, this didn't help. I also tried the **latest kernel 6.16-rc7**, and the issue **remains exactly the same**. ### Test 1: Trixie + Kernel 6.12 and 6.16-rc7 (minimal system, no X) **GRUB configuration:**

GRUB_CMDLINE_LINUX_DEFAULT="nomodeset vga=normal kvm.enable_virt_at_load=0 earlyprintk=serial,ttyS0,115200 console=tty0 console=ttyS0,115200 loglevel=7"
GRUB_TERMINAL="console serial"
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"

* ✅ Boot with **GTX 970** * ❌ Boot with **RTX 5070 Ti** => [logs](https://gist.github.com/aprovin/8e385c1b2a8875617ccb25f83cb2a609) --- ### Test 2: Trixie + Kernel 6.16-rc7 (more debug enabled) **GRUB configuration:**

GRUB_CMDLINE_LINUX_DEFAULT="nomodeset vga=normal earlyprintk=serial,ttyS0,115200 console=tty0 console=ttyS0,115200 loglevel=7 debug ignore_loglevel initcall_debug"
GRUB_TERMINAL="console serial"
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"

* ✅ Boot with **GTX 970** * ❌ Boot with **RTX 5070 Ti** => [logs](https://gist.github.com/aprovin/f5c99475f03f2f5e627ee09d0b7e9160) --- ### Test 3: Same as Test 2, but with **NVIDIA proprietary driver installed** Installed the latest NVIDIA open-source kernel modules: * [https://github.com/NVIDIA/open-gpu-kernel-modules](https://github.com/NVIDIA/open-gpu-kernel-modules) * ./NVIDIA-Linux-x86_64-575.64.03.run --no-opengl-files --no-kernel-modules Blacklist nouveau driver:

cat /etc/modprobe.d/blacklist-nvidia-nouveau.conf
blacklist nouveau
options nouveau modeset=0

* ✅ Boot with **GTX 970** * ❌ Boot with **RTX 5070 Ti** => [logs](https://gist.github.com/aprovin/4b781bb1a8e9bd9e8212e9e9f19455cd) --- ### Test 4: Same as Test 3, with **CSM disabled in BIOS** * ✅ Boot with **GTX 970** * ❌ Boot with **RTX 5070 Ti** => [logs](https://gist.github.com/aprovin/593b07bc67908372764ab47aea8f83c2) --- ## 🖥️ Hardware * **Motherboard**: ASUS PRIME B550M-A (BIOS fully updated) * **CPU**: AMD Ryzen 7 5800X3D (no integrated GPU) * **GPU**: NVIDIA RTX 5070 Ti * **Disk**: NVMe SSD * **Display**: Single monitor via HDMI (same issue with DisplayPort) ### Notes: * I’ve tried multiple HDMI/DP cables and different monitors — no change. * I've also tried **Ubuntu 25.04**, same result. --- ## Additional symptoms * The **boot process is extremely slow** with the RTX 5070 Ti (several minutes) * The same boot completes in **seconds with the GTX 970** --- ## I’m out of ideas... Has anyone managed to boot Linux with an RTX 5070 Ti? Any help would be greatly appreciated.

i did a search on google for "what version of linux uses theMediaTek 7902." The answer came back as: > The MediaTek Wi-Fi 6E MT7902 wireless network adapter is not natively > supported by the Linux kernel. However, the driver for the MT7902 was > added in the Linux 6.6.12 kernel series, and you can install these > recent kernels to enable support. Ubuntu recommends using its mainline > builds for this purpose. OK I installed LinuxMint 22.3 here as a dual boot. My Windows works with the mediatek but I have no idea how to add the Linux 6.6.12 kernel series. Any simple answers for a newbie?

We are currently testing tiered memory demotion on a machine equipped with a CXL device. To facilitate this, we created a specific script (https://github.com/hyun-sa/comem) and are using the memory.high setting within a cgroup to force memory demotion. These are the commands we used to enable demotion: echo 1 > /sys/kernel/mm/numa/demotion_enabled echo 2 > /proc/sys/kernel/numa_balancing The issue we're facing is that while demotion does occur, it proceeds extremely slowly—even slower than swapping to disk. Furthermore, during a 7-Zip benchmark, we observe a severe drop in CPU utilization, as if some process is causing a lock. This is our running example (7zr b -md25 while memory is limited as 8G by memory.high) 7-Zip (r) 23.01 (x64) : Igor Pavlov : Public domain : 2023-06-20 64-bit locale=C.UTF-8 Threads:128 OPEN_MAX:1024 d25 Compiler: 13.2.0 GCC 13.2.0: SSE2 Linux : 6.15.6 : #1 SMP PREEMPT_DYNAMIC Tue Jul 15 06:39:48 UTC 2025 : x86_64 PageSize:4KB THP:madvise hwcap:2 hwcap2:2 AMD EPYC 9554 64-Core Processor (A10F11) 1T CPU Freq (MHz): 3710 3731 3732 3733 3733 3732 3732 64T CPU Freq (MHz): 6329% 3674 6006% 3495 RAM size: 386638 MB, # CPU hardware threads: 128 RAM usage: 28478 MB, # Benchmark threads: 128 Compressing | Decompressing Dict Speed Usage R/U Rating | Speed Usage R/U Rating KiB/s % MIPS MIPS | KiB/s % MIPS MIPS 22: 477942 10925 4256 464943 | 5843081 12451 4001 498193 23: 337115 8816 3896 343480 | 5826376 12606 3999 504053 24: 1785 108 1772 1919 | 5654618 12631 3928 496161 25: 960 63 1739 1097 | 1767869 4606 3415 157287 ---------------------------------- | ------------------------------ Avr: 204451 4978 2916 202860 | 4772986 10573 3836 413924 Tot: 7776 3376 308392 execution_time(ms): 2807639 Is there a potential misunderstanding of how cgroups function or a misconfiguration in my setup that could be causing this behavior? Our machine specifications are as follows: Mainboard : Supermicro H13SSL-NT CPU : Epyc 9554 (nps 1) Dram : 128G CXL device : SMART Modular Technologies Device c241 OS : Ubuntu 24.04 LTS Kernel : Linux 6.15.6 numactl -H available: 2 nodes (0-1) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 node 0 size: 128640 MB node 0 free: 117909 MB node 1 cpus: node 1 size: 257998 MB node 1 free: 257840 MB node distances: node 0 1 0: 10 50 1: 255 10 Thank you for your help.

I'm trying to figure out which specific Python process or executable was killed by the Linux OOM killer. In /var/log/messages I get this: Aug 18 03:19:11 169 kernel: [ 7747] 0 7748 3226957 2875051 5692 0 0 python (notice it just say name = "python") and this: Aug 18 03:19:11 169 kernel: Killed process 7748 (python) total-vm:12907828kB, anon-rss:11500204kB, file-rss:0kB (again notice it just says the process was "python") Ideally a log file for the process would have the PID somewhere. But suppose the logs wrapped (or suppose the process doesn't log the PID anywhere). Does Linux provide a way to figure out the full command that was executed for the process? It would be nice to configure Linux's OOM killer to display the full name in the process table, such as: /usr/bin/python /usr/lib/python2.7/site-packages/foo.pyc Or maybe at the time of the OOM error Linux stores off some of the process details somewhere? i.e. copy the processes from /proc to X? (wishful thinking) ### NOTE: ### This question is very similar to this question: https://stackoverflow.com/questions/624857/finding-which-process-was-killed-by-linux-oom-killer But it fell short of what I'm trying to figure out.

How can I take snippets from the Linux kernel drivers' code, for example this [drm_fb_helper_hotplug_event](https://github.com/torvalds/linux/blob/6832a9317eee280117cd695fa885b2b7a7a38daf/drivers/gpu/drm/drm_fb_helper.c#L1943) function inside drivers/gpu/drm/drm_fb_helper.c, and compile a binary file that I can run to conveniently achieve a particular action in the kernel? In my case, I'd like to call the function arbitrarily to hopefully force a reset of the list of video connectors detected by the kernel, because of monitor output issues. There are probably better ways of achieving this, such as making an out-of-tree module, but I'm not sure how I can do that here. I want to compile an executable that I run from userspace, which will get my task done. So far as a proof of concept, I have tried to get printk/printfs done using only gcc to compile a binary instead of make: HOSTCC=gcc-11 CC=gcc-11 gcc ../drivers/gpu/drm/testing_printout.c -o printAMessage -I. (Compiling an older version that needs GCC 11, after a cd include using -I as the [equivalent to CPATH](https://stackoverflow.com/questions/558803/how-can-i-add-a-default-include-path-for-gcc-in-linux).) But this comes up with problems.

./linux/atomic.h:7:10: fatal error: asm/atomic.h: No such file or directory

So I made a symlink; ln -s asm-generic asm But I still get other header file related errors and warnings:

./linux/thread_info.h:60:10: fatal error: asm/thread_info.h: No such file or directory

I have tried appending ARCH=x86 to the gcc command but it didn't help. Other errors like

./linux/stddef.h:11:9: error: cannot use keyword ‘false’ as enumeration constant
./linux/stddef.h:11:9: note: ‘false’ is a keyword with ‘-std=c23’ onwards
./linux/types.h:30:33: error: ‘bool’ cannot be defined via ‘typedef’
./linux/types.h:30:33: note: ‘bool’ is a keyword with ‘-std=c23’ onwards
...
./linux/atomic/atomic-arch-fallback.h:2245:35: error: unknown type name ‘atomic64_t’; did you mean ‘atomic_t’?

tell me something is wrong with the include files and the CLAGS. What am I missing? Seeing the -std=c23 note made me look at the Makefile at the root of the source directory:

LINUXINCLUDE    := \
		-I$(srctree)/arch/$(SRCARCH)/include \
		-I$(objtree)/arch/$(SRCARCH)/include/generated \
		$(if $(building_out_of_srctree),-I$(srctree)/include) \
		-I$(objtree)/include \
		$(USERINCLUDE)

KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
		   -Werror=implicit-function-declaration -Werror=implicit-int \
		   -Werror=return-type -Wno-format-security \
		   -std=gnu89

I guess using gcc directly instead of the makefiles is really inconvenient. What is the usual way of achieving my goal?

How do I kill a process that cannot be killed?

user@kubuntu22:~$ ps -ef |grep smbd
nobody   3532354       1  0 16:30 ?        00:00:00 /usr/sbin/smbd --foreground --no-process-group

user@kubuntu22:~$ sudo killall smbd

user@kubuntu22:~$ ps -ef |grep smbd
nobody   3532354       1  0 16:30 ?        00:00:00 /usr/sbin/smbd --foreground --no-process-group

user@kubuntu22:~$ sudo killall -KILL smbd

user@kubuntu22:~$ ps -ef |grep smbd
nobody   3532354       1  0 16:30 ?        00:00:00 /usr/sbin/smbd --foreground --no-process-group

user@kubuntu22:~$ sudo kill -9 3532354

user@kubuntu22:~$ ps -ef |grep smbd
nobody   3532354       1  0 16:30 ?        00:00:00 /usr/sbin/smbd --foreground --no-process-group

System information: (Ubuntu 22.04.5 LTS jammy Linux 6.5.0-35-generic x86_64) Edit:

user@kubuntu22:~$ ps ax |grep smbd
3532354 ?        D      0:00 /usr/sbin/smbd --foreground --no-process-group

I guess it's stuck in the "erroneous uninterruptible sleep " state (D) And it has the network port open so running another smbd works but I can't connect.

@kubuntu22:~$ sudo netstat -tunap |grep smbd
tcp        0      0 0.0.0.0:139             0.0.0.0:*               LISTEN      3564116/smbd        
tcp        0      0 0.0.0.0:445             0.0.0.0:*               LISTEN      3564116/smbd        
tcp     1117      0 127.0.0.1:445           127.0.0.1:41882         CLOSE_WAIT  3532354/smbd        
tcp6       0      0 :::139                  :::*                    LISTEN      3564116/smbd        
tcp6       0      0 :::445                  :::*                    LISTEN      3564116/smbd