From 506ada89629ec7059b96ecfb0dc7d33ece0103ca Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 17:05:56 -0700 Subject: bpf: mark a NULL kfunc argument precise check_kfunc_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value. Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com Signed-off-by: Alexei Starovoitov --- drivers/dax/hmem/device.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) create mode 100644 drivers/dax/hmem/device.c (limited to 'drivers/dax/hmem/device.c') diff --git a/drivers/dax/hmem/device.c b/drivers/dax/hmem/device.c new file mode 100644 index 000000000..d70359b43 --- /dev/null +++ b/drivers/dax/hmem/device.c @@ -0,0 +1,103 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include "../bus.h" + +static bool nohmem; +module_param_named(disable, nohmem, bool, 0444); + +static bool platform_initialized; +static DEFINE_MUTEX(hmem_resource_lock); +static struct resource hmem_active = { + .name = "HMEM devices", + .start = 0, + .end = -1, + .flags = IORESOURCE_MEM, +}; + +int walk_hmem_resources(struct device *host, walk_hmem_fn fn) +{ + struct resource *res; + int rc = 0; + + mutex_lock(&hmem_resource_lock); + for (res = hmem_active.child; res; res = res->sibling) { + rc = fn(host, (int) res->desc, res); + if (rc) + break; + } + mutex_unlock(&hmem_resource_lock); + return rc; +} +EXPORT_SYMBOL_GPL(walk_hmem_resources); + +static void hmem_work(struct work_struct *work) +{ + /* place holder until dax_hmem driver attaches */ +} + +static struct hmem_platform_device hmem_platform = { + .pdev = { + .name = "hmem_platform", + .id = 0, + }, + .work = __WORK_INITIALIZER(hmem_platform.work, hmem_work), +}; + +static void __hmem_register_resource(int target_nid, struct resource *res) +{ + struct resource *new; + int rc; + + new = __request_region(&hmem_active, res->start, resource_size(res), "", + 0); + if (!new) { + pr_debug("hmem range %pr already active\n", res); + return; + } + + new->desc = target_nid; + + if (platform_initialized) + return; + + rc = platform_device_register(&hmem_platform.pdev); + if (rc) { + pr_err_once("failed to register device-dax hmem_platform device\n"); + return; + } + + platform_initialized = true; +} + +void hmem_register_resource(int target_nid, struct resource *res) +{ + if (nohmem) + return; + + mutex_lock(&hmem_resource_lock); + __hmem_register_resource(target_nid, res); + mutex_unlock(&hmem_resource_lock); +} + +static __init int hmem_register_one(struct resource *res, void *data) +{ + hmem_register_resource(phys_to_target_node(res->start), res); + + return 0; +} + +static __init int hmem_init(void) +{ + walk_soft_reserve_res(0, -1, NULL, hmem_register_one); + return 0; +} + +/* + * As this is a fallback for address ranges unclaimed by the ACPI HMAT + * parsing it must be at an initcall level greater than hmat_init(). + */ +device_initcall(hmem_init); -- cgit v1.3.1