user/sven/linux.git/include, branch v6.6.79

x86/i8253: Disable PIT timer 0 when not in use

2025-02-21T12:57:27Z

commit 70e6b7d9ae3c63df90a7bba7700e8d5c300c3c60 upstream. Leaving the PIT interrupt running can cause noticeable steal time for virtual guests. The VMM generally has a timer which toggles the IRQ input to the PIC and I/O APIC, which takes CPU time away from the guest. Even on real hardware, running the counter may use power needlessly (albeit not much). Make sure it's turned off if it isn't going to be used. Signed-off-by: David Woodhouse Signed-off-by: Thomas Gleixner Tested-by: Michael Kelley Link: https://lore.kernel.org/all/20240802135555.564941-1-dwmw2@infradead.org Signed-off-by: Greg Kroah-Hartman

net: add dev_net_rcu() helper

2025-02-21T12:57:20Z

[ Upstream commit 482ad2a4ace2740ca0ff1cbc8f3c7f862f3ab507 ] dev->nd_net can change, readers should either use rcu_read_lock() or RTNL. We currently use a generic helper, dev_net() with no debugging support. We probably have many hidden bugs. Add dev_net_rcu() helper for callers using rcu_read_lock() protection. Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250205155120.1676781-2-edumazet@google.com Signed-off-by: Jakub Kicinski Stable-dep-of: 71b8471c93fa ("ipv4: use RCU protection in ipv4_default_advmss()") Signed-off-by: Sasha Levin

net: treat possible_net_t net pointer as an RCU one and add read_pnet_rcu()

2025-02-21T12:57:20Z

[ Upstream commit 2034d90ae41ae93e30d492ebcf1f06f97a9cfba6 ] Make the net pointer stored in possible_net_t structure annotated as an RCU pointer. Change the access helpers to treat it as such. Introduce read_pnet_rcu() helper to allow caller to dereference the net pointer under RCU read lock. Signed-off-by: Jiri Pirko Reviewed-by: Simon Horman Signed-off-by: David S. Miller Stable-dep-of: 71b8471c93fa ("ipv4: use RCU protection in ipv4_default_advmss()") Signed-off-by: Sasha Levin

ipv4: add RCU protection to ip4_dst_hoplimit()

2025-02-21T12:57:20Z

[ Upstream commit 469308552ca4560176cfc100e7ca84add1bebd7c ] ip4_dst_hoplimit() must use RCU protection to make sure the net structure it reads does not disappear. Fixes: fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob") Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250205155120.1676781-3-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

cgroup: fix race between fork and cgroup.kill

2025-02-21T12:57:17Z

commit b69bb476dee99d564d65d418e9a20acca6f32c3f upstream. Tejun reported the following race between fork() and cgroup.kill at [1]. Tejun: I was looking at cgroup.kill implementation and wondering whether there could be a race window. So, __cgroup_kill() does the following: k1. Set CGRP_KILL. k2. Iterate tasks and deliver SIGKILL. k3. Clear CGRP_KILL. The copy_process() does the following: c1. Copy a bunch of stuff. c2. Grab siglock. c3. Check fatal_signal_pending(). c4. Commit to forking. c5. Release siglock. c6. Call cgroup_post_fork() which puts the task on the css_set and tests CGRP_KILL. The intention seems to be that either a forking task gets SIGKILL and terminates on c3 or it sees CGRP_KILL on c6 and kills the child. However, I don't see what guarantees that k3 can't happen before c6. ie. After a forking task passes c5, k2 can take place and then before the forking task reaches c6, k3 can happen. Then, nobody would send SIGKILL to the child. What am I missing? This is indeed a race. One way to fix this race is by taking cgroup_threadgroup_rwsem in write mode in __cgroup_kill() as the fork() side takes cgroup_threadgroup_rwsem in read mode from cgroup_can_fork() to cgroup_post_fork(). However that would be heavy handed as this adds one more potential stall scenario for cgroup.kill which is usually called under extreme situation like memory pressure. To fix this race, let's maintain a sequence number per cgroup which gets incremented on __cgroup_kill() call. On the fork() side, the cgroup_can_fork() will cache the sequence number locally and recheck it against the cgroup's sequence number at cgroup_post_fork() site. If the sequence numbers mismatch, it means __cgroup_kill() can been called and we should send SIGKILL to the newly created task. Reported-by: Tejun Heo Closes: https://lore.kernel.org/all/Z5QHE2Qn-QZ6M-KW@slm.duckdns.org/ [1] Fixes: 661ee6280931 ("cgroup: introduce cgroup.kill") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Shakeel Butt Reviewed-by: Michal Koutný Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman

efi: Avoid cold plugged memory for placing the kernel

2025-02-21T12:57:17Z

commit ba69e0750b0362870294adab09339a0c39c3beaf upstream. UEFI 2.11 introduced EFI_MEMORY_HOT_PLUGGABLE to annotate system memory regions that are 'cold plugged' at boot, i.e., hot pluggable memory that is available from early boot, and described as system RAM by the firmware. Existing loaders and EFI applications running in the boot context will happily use this memory for allocating data structures that cannot be freed or moved at runtime, and this prevents the memory from being unplugged. Going forward, the new EFI_MEMORY_HOT_PLUGGABLE attribute should be tested, and memory annotated as such should be avoided for such allocations. In the EFI stub, there are a couple of occurrences where, instead of the high-level AllocatePages() UEFI boot service, a low-level code sequence is used that traverses the EFI memory map and carves out the requested number of pages from a free region. This is needed, e.g., for allocating as low as possible, or for allocating pages at random. While AllocatePages() should presumably avoid special purpose memory and cold plugged regions, this manual approach needs to incorporate this logic itself, in order to prevent the kernel itself from ending up in a hot unpluggable region, preventing it from being unplugged. So add the EFI_MEMORY_HOTPLUGGABLE macro definition, and check for it where appropriate. Cc: stable@vger.kernel.org Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman

block: cleanup and fix batch completion adding conditions

2025-02-21T12:57:09Z

[ Upstream commit 1f47ed294a2bd577d5ae43e6e28e1c9a3be4a833 ] The conditions for whether or not a request is allowed adding to a completion batch are a bit hard to read, and they also have a few issues. One is that ioerror may indeed be a random value on passthrough, and it's being checked unconditionally of whether or not the given request is a passthrough request or not. Rewrite the conditions to be separate for easier reading, and only check ioerror for non-passthrough requests. This fixes an issue with bio unmapping on passthrough, where it fails getting added to a batch. This both leads to suboptimal performance, and may trigger a potential schedule-under-atomic condition for polled passthrough IO. Fixes: f794f3351f26 ("block: add support for blk_mq_end_request_batch()") Link: https://lore.kernel.org/r/20575f0a-656e-4bb3-9d82-dec6c7e3a35c@kernel.dk Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

vrf: use RCU protection in l3mdev_l3_out()

2025-02-21T12:57:07Z

[ Upstream commit 6d0ce46a93135d96b7fa075a94a88fe0da8e8773 ] l3mdev_l3_out() can be called without RCU being held: raw_sendmsg() ip_push_pending_frames() ip_send_skb() ip_local_out() __ip_local_out() l3mdev_ip_out() Add rcu_read_lock() / rcu_read_unlock() pair to avoid a potential UAF. Fixes: a8e3e1a9f020 ("net: l3mdev: Add hook to output path") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250207135841.1948589-7-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

rv: Reset per-task monitors also for idle tasks

2025-02-17T08:40:32Z

commit 8259cb14a70680553d5e82d65d1302fe589e9b39 upstream. RV per-task monitors are implemented through a monitor structure available for each task_struct. This structure is reset every time the monitor is (re-)started, to avoid inconsistencies if the monitor was activated previously. To do so, we reset the monitor on all threads using the macro for_each_process_thread. However, this macro excludes the idle tasks on each CPU. Idle tasks could be considered tasks on their own right and it should be up to the model whether to ignore them or not. Reset monitors also on the idle tasks for each present CPU whenever we reset all per-task monitors. Cc: stable@vger.kernel.org Cc: Juri Lelli Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: John Kacur Link: https://lore.kernel.org/20250115151547.605750-2-gmonaco@redhat.com Fixes: 792575348ff7 ("rv/include: Add deterministic automata monitor definition via C macros") Signed-off-by: Gabriele Monaco Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman

scsi: ufs: core: Fix the HIGH/LOW_TEMP Bit Definitions

2025-02-17T08:40:20Z

commit 1b3e2d4ec0c5848776cc56d2624998aa5b2f0d27 upstream. According to the UFS Device Specification, the dExtendedUFSFeaturesSupport defines the support for TOO_HIGH_TEMPERATURE as bit[4] and the TOO_LOW_TEMPERATURE as bit[5]. Correct the code to match with the UFS device specification definition. Cc: stable@vger.kernel.org Fixes: e88e2d32200a ("scsi: ufs: core: Probe for temperature notification support") Signed-off-by: Bao D. Nguyen Link: https://lore.kernel.org/r/69992b3e3e3434a5c7643be5a64de48be892ca46.1736793068.git.quic_nguyenb@quicinc.com Reviewed-by: Avri Altman Reviewed-by: Peter Wang Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman