From 2bc6b218717b9d08f466f88209251d54bc09b207 Mon Sep 17 00:00:00 2001 From: Fuad Tabba Date: Tue, 22 Sep 2026 19:14:30 +0100 Subject: arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 __init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2. PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a write from EL0 reaches the trap and takes the host down without a panic message. Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9 bits. Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9") Cc: stable@vger.kernel.org Signed-off-by: Fuad Tabba Reviewed-by: Anshuman Khandual Reviewed-by: Oliver Upton Signed-off-by: Will Deacon --- lib/timerqueue.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) create mode 100644 lib/timerqueue.c (limited to 'lib/timerqueue.c') diff --git a/lib/timerqueue.c b/lib/timerqueue.c new file mode 100644 index 000000000..e2a1e08cb --- /dev/null +++ b/lib/timerqueue.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Generic Timer-queue + * + * Manages a simple queue of timers, ordered by expiration time. + * Uses rbtrees for quick list adds and expiration. + * + * NOTE: All of the following functions need to be serialized + * to avoid races. No locking is done by this library code. + */ + +#include +#include +#include +#include + +#define __node_2_tq(_n) \ + rb_entry((_n), struct timerqueue_node, node) + +static inline bool __timerqueue_less(struct rb_node *a, const struct rb_node *b) +{ + return __node_2_tq(a)->expires < __node_2_tq(b)->expires; +} + +/** + * timerqueue_add - Adds timer to timerqueue. + * + * @head: head of timerqueue + * @node: timer node to be added + * + * Adds the timer node to the timerqueue, sorted by the node's expires + * value. Returns true if the newly added timer is the first expiring timer in + * the queue. + */ +bool timerqueue_add(struct timerqueue_head *head, struct timerqueue_node *node) +{ + /* Make sure we don't add nodes that are already added */ + WARN_ON_ONCE(!RB_EMPTY_NODE(&node->node)); + + return rb_add_cached(&node->node, &head->rb_root, __timerqueue_less); +} +EXPORT_SYMBOL_GPL(timerqueue_add); + +/** + * timerqueue_del - Removes a timer from the timerqueue. + * + * @head: head of timerqueue + * @node: timer node to be removed + * + * Removes the timer node from the timerqueue. Returns true if the queue is + * not empty after the remove. + */ +bool timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node) +{ + WARN_ON_ONCE(RB_EMPTY_NODE(&node->node)); + + rb_erase_cached(&node->node, &head->rb_root); + RB_CLEAR_NODE(&node->node); + + return !RB_EMPTY_ROOT(&head->rb_root.rb_root); +} +EXPORT_SYMBOL_GPL(timerqueue_del); + +/** + * timerqueue_iterate_next - Returns the timer after the provided timer + * + * @node: Pointer to a timer. + * + * Provides the timer that is after the given node. This is used, when + * necessary, to iterate through the list of timers in a timer list + * without modifying the list. + */ +struct timerqueue_node *timerqueue_iterate_next(struct timerqueue_node *node) +{ + struct rb_node *next; + + if (!node) + return NULL; + next = rb_next(&node->node); + if (!next) + return NULL; + return container_of(next, struct timerqueue_node, node); +} +EXPORT_SYMBOL_GPL(timerqueue_iterate_next); + +#define __node_2_tq_linked(_n) \ + container_of(rb_entry((_n), struct rb_node_linked, node), struct timerqueue_linked_node, node) + +static __always_inline bool __tq_linked_less(struct rb_node *a, const struct rb_node *b) +{ + return __node_2_tq_linked(a)->expires < __node_2_tq_linked(b)->expires; +} + +bool timerqueue_linked_add(struct timerqueue_linked_head *head, struct timerqueue_linked_node *node) +{ + return rb_add_linked(&node->node, &head->rb_root, __tq_linked_less); +} +EXPORT_SYMBOL_GPL(timerqueue_linked_add); -- cgit v1.3.1