user/sven/linux.git/Documentation, branch v6.12.55

arm64: errata: Apply workarounds for Neoverse-V3AE

2025-10-23T14:20:47Z

commit 0c33aa1804d101c11ba1992504f17a42233f0e11 upstream. Neoverse-V3AE is also affected by erratum #3312417, as described in its Software Developer Errata Notice (SDEN) document: Neoverse V3AE (MP172) SDEN v9.0, erratum 3312417 https://developer.arm.com/documentation/SDEN-2615521/9-0/ Enable the workaround for Neoverse-V3AE, and document this. Signed-off-by: Mark Rutland Cc: James Morse Cc: Will Deacon Cc: Catalin Marinas Signed-off-by: Ryan Roberts Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

doc: fix seg6_flowlabel path

2025-10-23T14:20:29Z

[ Upstream commit 0b4b77eff5f8cd9be062783a1c1e198d46d0a753 ] This sysctl is not per interface; it's global per netns. Fixes: 292ecd9f5a94 ("doc: move seg6_flowlabel to seg6-sysctl.rst") Reported-by: Philippe Guibert Signed-off-by: Nicolas Dichtel Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

fs: Add 'initramfs_options' to set initramfs mount options

2025-10-19T14:34:06Z

[ Upstream commit 278033a225e13ec21900f0a92b8351658f5377f2 ] When CONFIG_TMPFS is enabled, the initial root filesystem is a tmpfs. By default, a tmpfs mount is limited to using 50% of the available RAM for its content. This can be problematic in memory-constrained environments, particularly during a kdump capture. In a kdump scenario, the capture kernel boots with a limited amount of memory specified by the 'crashkernel' parameter. If the initramfs is large, it may fail to unpack into the tmpfs rootfs due to insufficient space. This is because to get X MB of usable space in tmpfs, 2*X MB of memory must be available for the mount. This leads to an OOM failure during the early boot process, preventing a successful crash dump. This patch introduces a new kernel command-line parameter, initramfs_options, which allows passing specific mount options directly to the rootfs when it is first mounted. This gives users control over the rootfs behavior. For example, a user can now specify initramfs_options=size=75% to allow the tmpfs to use up to 75% of the available memory. This can significantly reduce the memory pressure for kdump. Consider a practical example: To unpack a 48MB initramfs, the tmpfs needs 48MB of usable space. With the default 50% limit, this requires a memory pool of 96MB to be available for the tmpfs mount. The total memory requirement is therefore approximately: 16MB (vmlinuz) + 48MB (loaded initramfs) + 48MB (unpacked kernel) + 96MB (for tmpfs) + 12MB (runtime overhead) ≈ 220MB. By using initramfs_options=size=75%, the memory pool required for the 48MB tmpfs is reduced to 48MB / 0.75 = 64MB. This reduces the total memory requirement by 32MB (96MB - 64MB), allowing the kdump to succeed with a smaller crashkernel size, such as 192MB. An alternative approach of reusing the existing rootflags parameter was considered. However, a new, dedicated initramfs_options parameter was chosen to avoid altering the current behavior of rootflags (which applies to the final root filesystem) and to prevent any potential regressions. Also add documentation for the new kernel parameter "initramfs_options" This approach is inspired by prior discussions and patches on the topic. Ref: https://www.lightofdawn.org/blog/?viewDetailed=00128 Ref: https://landley.net/notes-2015.html#01-01-2015 Ref: https://lkml.org/lkml/2021/6/29/783 Ref: https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html#what-is-rootfs Signed-off-by: Lichen Liu Link: https://lore.kernel.org/20250815121459.3391223-1-lichliu@redhat.com Tested-by: Rob Landley Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

dt-bindings: phy: rockchip-inno-csi-dphy: make power-domains non-required

2025-10-19T14:33:45Z

commit c254815b02673cc77a84103c4c0d6197bd90c0ef upstream. There are variants of the Rockchip Innosilicon CSI DPHY (e.g., the RK3568 variant) that are powered on by default as they are part of the ALIVE power domain. Remove 'power-domains' from the required properties in order to avoid false positives. Fixes: 22c8e0a69b7f ("dt-bindings: phy: add compatible for rk356x to rockchip-inno-csi-dphy") Cc: stable@kernel.org Reviewed-by: Krzysztof Kozlowski Signed-off-by: Michael Riesch Link: https://lore.kernel.org/r/20250616-rk3588-csi-dphy-v4-2-a4f340a7f0cf@collabora.com Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman

Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram

2025-10-15T10:00:13Z

[ Upstream commit 8c716e87ea33519920811338100d6d8a7fb32456 ] Section heading for sched_waking histogram is shown as normal paragraph instead due to codeblock marker for the following diagram being in the same line as the section underline. Separate them. Fixes: daceabf1b494 ("tracing/doc: Fix ascii-art in histogram-design.rst") Reviewed-by: Tom Zanussi Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Bagas Sanjaya Acked-by: Steven Rostedt (Google) Signed-off-by: Jonathan Corbet Message-ID: <20250916054202.582074-5-bagasdotme@gmail.com> Signed-off-by: Sasha Levin

platform/x86: lg-laptop: Fix WMAB call in fan_mode_store()

2025-10-02T11:44:12Z

[ Upstream commit 3ed17349f18774c24505b0c21dfbd3cc4f126518 ] When WMAB is called to set the fan mode, the new mode is read from either bits 0-1 or bits 4-5 (depending on the value of some other EC register). Thus when WMAB is called with bits 4-5 zeroed and called again with bits 0-1 zeroed, the second call undoes the effect of the first call. This causes writes to /sys/devices/platform/lg-laptop/fan_mode to have no effect (and causes reads to always report a status of zero). Fix this by calling WMAB once, with the mode set in bits 0,1 and 4,5. When the fan mode is returned from WMAB it always has this form, so there is no need to preserve the other bits. As a bonus, the driver now supports the "Performance" fan mode seen in the LG-provided Windows control app, which provides less aggressive CPU throttling but louder fan noise and shorter battery life. Also, correct the documentation to reflect that 0 corresponds to the default mode (what the Windows app calls "Optimal") and 1 corresponds to the silent mode. Fixes: dbf0c5a6b1f8 ("platform/x86: Add LG Gram laptop special features driver") Link: https://bugzilla.kernel.org/show_bug.cgi?id=204913#c4 Signed-off-by: Daniel Lee Link: https://patch.msgid.link/MN2PR06MB55989CB10E91C8DA00EE868DDC1CA@MN2PR06MB5598.namprd06.prod.outlook.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen Signed-off-by: Sasha Levin

mptcp: pm: nl: announce deny-join-id0 flag

2025-09-25T09:13:50Z

commit 2293c57484ae64c9a3c847c8807db8c26a3a4d41 upstream. During the connection establishment, a peer can tell the other one that it cannot establish new subflows to the initial IP address and port by setting the 'C' flag [1]. Doing so makes sense when the sender is behind a strict NAT, operating behind a legacy Layer 4 load balancer, or using anycast IP address for example. When this 'C' flag is set, the path-managers must then not try to establish new subflows to the other peer's initial IP address and port. The in-kernel PM has access to this info, but the userspace PM didn't. The RFC8684 [1] is strict about that: (...) therefore the receiver MUST NOT try to open any additional subflows toward this address and port. So it is important to tell the userspace about that as it is responsible for the respect of this flag. When a new connection is created and established, the Netlink events now contain the existing but not currently used 'flags' attribute. When MPTCP_PM_EV_FLAG_DENY_JOIN_ID0 is set, it means no other subflows to the initial IP address and port -- info that are also part of the event -- can be established. Link: https://datatracker.ietf.org/doc/html/rfc8684#section-3.1-20.6 [1] Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment") Reported-by: Marek Majkowski Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/532 Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250912-net-mptcp-pm-uspace-deny_join_id0-v1-2-40171884ade8@kernel.org Signed-off-by: Jakub Kicinski [ Conflicts in mptcp_pm.yaml, because the indentation has been modified in commit ec362192aa9e ("netlink: specs: fix up indentation errors"), which is not in this version. Applying the same modifications, but at a different level. ] Signed-off-by: Matthieu Baerts (NGI0) Signed-off-by: Greg Kroah-Hartman

x86/bugs: KVM: Add support for SRSO_MSR_FIX

2025-09-25T09:13:49Z

commit 8442df2b49ed9bcd67833ad4f091d15ac91efd00 upstream. Add support for CPUID Fn8000_0021_EAX[31] (SRSO_MSR_FIX). If this bit is 1, it indicates that software may use MSR BP_CFG[BpSpecReduce] to mitigate SRSO. Enable BpSpecReduce to mitigate SRSO across guest/host boundaries. Switch back to enabling the bit when virtualization is enabled and to clear the bit when virtualization is disabled because using a MSR slot would clear the bit when the guest is exited and any training the guest has done, would potentially influence the host kernel when execution enters the kernel and hasn't VMRUN the guest yet. More detail on the public thread in Link below. Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20241202120416.6054-1-bp@kernel.org Signed-off-by: Harshit Mogalapalli Signed-off-by: Greg Kroah-Hartman

docs: networking: can: change bcm_msg_head frames member to support flexible array

2025-09-19T14:35:49Z

[ Upstream commit 641427d5bf90af0625081bf27555418b101274cd ] The documentation of the 'bcm_msg_head' struct does not match how it is defined in 'bcm.h'. Changed the frames member to a flexible array, matching the definition in the header file. See commit 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members") Signed-off-by: Alex Tran Acked-by: Oliver Hartkopp Link: https://patch.msgid.link/20250904031709.1426895-1-alex.t.tran@gmail.com Fixes: 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members") Link: https://bugzilla.kernel.org/show_bug.cgi?id=217783 Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

dt-bindings: serial: brcm,bcm7271-uart: Constrain clocks

2025-09-19T14:35:48Z

commit ee047e1d85d73496541c54bd4f432c9464e13e65 upstream. Lists should have fixed constraints, because binding must be specific in respect to hardware, thus add missing constraints to number of clocks. Cc: stable Fixes: 88a499cd70d4 ("dt-bindings: Add support for the Broadcom UART driver") Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20250812121630.67072-2-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman