July 2025 - Linux-stable-mirror

[PATCH v2] vhost/net: Replace wait_queue with completion in ubufs reference

by Nikolay Kuratov

When operating on struct vhost_net_ubuf_ref, the following execution sequence is theoretically possible: CPU0 is finalizing DMA operation CPU1 is doing VHOST_NET_SET_BACKEND // &ubufs->refcount == 2 vhost_net_ubuf_put() vhost_net_ubuf_put_wait_and_free(oldubufs) vhost_net_ubuf_put_and_wait() vhost_net_ubuf_put() int r = atomic_sub_return(1, &ubufs->refcount); // r = 1 int r = atomic_sub_return(1, &ubufs->refcount); // r = 0 wait_event(ubufs->wait, !atomic_read(&ubufs->refcount)); // no wait occurs here because condition is already true kfree(ubufs); if (unlikely(!r)) wake_up(&ubufs->wait); // use-after-free This leads to use-after-free on ubufs access. This happens because CPU1 skips waiting for wake_up() when refcount is already zero. To prevent that use a completion instead of wait_queue as the ubufs notification mechanism. wait_for_completion() guarantees that there will be complete() call prior to its return. We also need to reinit completion in vhost_net_flush(), because refcnt == 0 does not mean freeing in that case. Cc: stable(a)vger.kernel.org Fixes: 0ad8b480d6ee9 ("vhost: fix ref cnt checking deadlock") Reported-by: Andrey Ryabinin <arbn(a)yandex-team.com> Suggested-by: Andrey Smetanin <asmetanin(a)yandex-team.ru> Suggested-by: Hillf Danton <hdanton(a)sina.com> Tested-by: Lei Yang <leiyang(a)redhat.com> (v1) Signed-off-by: Nikolay Kuratov <kniv(a)yandex-team.ru> --- v2: * move reinit_completion() into vhost_net_flush(), thanks to Hillf Danton * add Tested-by: Lei Yang * check that usages of put_and_wait() are consistent across LTS kernels drivers/vhost/net.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 7cbfc7d718b3..69e1bfb9627e 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -94,7 +94,7 @@ struct vhost_net_ubuf_ref { * >1: outstanding ubufs */ atomic_t refcount; - wait_queue_head_t wait; + struct completion wait; struct vhost_virtqueue *vq; }; @@ -240,7 +240,7 @@ vhost_net_ubuf_alloc(struct vhost_virtqueue *vq, bool zcopy) if (!ubufs) return ERR_PTR(-ENOMEM); atomic_set(&ubufs->refcount, 1); - init_waitqueue_head(&ubufs->wait); + init_completion(&ubufs->wait); ubufs->vq = vq; return ubufs; } @@ -249,14 +249,14 @@ static int vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) { int r = atomic_sub_return(1, &ubufs->refcount); if (unlikely(!r)) - wake_up(&ubufs->wait); + complete_all(&ubufs->wait); return r; } static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) { vhost_net_ubuf_put(ubufs); - wait_event(ubufs->wait, !atomic_read(&ubufs->refcount)); + wait_for_completion(&ubufs->wait); } static void vhost_net_ubuf_put_wait_and_free(struct vhost_net_ubuf_ref *ubufs) @@ -1381,6 +1381,7 @@ static void vhost_net_flush(struct vhost_net *n) mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); n->tx_flush = false; atomic_set(&n->vqs[VHOST_NET_VQ_TX].ubufs->refcount, 1); + reinit_completion(&n->vqs[VHOST_NET_VQ_TX].ubufs->wait); mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex); } } -- 2.34.1

1 week, 4 days

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[PATCH v6] riscv: hwprobe: Fix stale vDSO data for late-initialized keys at boot

by Jingwei Wang

The hwprobe vDSO data for some keys, like MISALIGNED_VECTOR_PERF, is determined by an asynchronous kthread. This can create a race condition where the kthread finishes after the vDSO data has already been populated, causing userspace to read stale values. To fix this race, a new 'ready' flag is added to the vDSO data, initialized to 'false' during late_initcall. This flag is checked by both the vDSO's user-space code and the riscv_hwprobe syscall. The syscall serves as a one-time gate, using a completion to wait for any pending probes before populating the data and setting the flag to 'true', thus ensuring userspace reads fresh values on its first request. Reported-by: Tsukasa OI <research_trasio(a)irq.a4lg.com> Closes: https://lore.kernel.org/linux-riscv/760d637b-b13b-4518-b6bf-883d55d44e7f@ir… Fixes: e7c9d66e313b ("RISC-V: Report vector unaligned access speed hwprobe") Cc: Palmer Dabbelt <palmer(a)dabbelt.com> Cc: Alexandre Ghiti <alexghiti(a)rivosinc.com> Cc: Olof Johansson <olof(a)lixom.net> Cc: stable(a)vger.kernel.org Co-developed-by: Palmer Dabbelt <palmer(a)dabbelt.com> Signed-off-by: Jingwei Wang <wangjingwei(a)iscas.ac.cn> --- Changes in v6: - Based on Palmer's feedback, reworked the synchronization to be on-demand, deferring the wait until the first hwprobe syscall via a 'ready' flag. This avoids the boot-time regression from v5's approach. Changes in v5: - Reworked the synchronization logic to a robust "sentinel-count" pattern based on feedback from Alexandre. - Fixed a "multiple definition" linker error for nommu builds by changing the header-file stub functions to `static inline`, as pointed out by Olof. - Updated the commit message to better explain the rationale for moving the vDSO initialization to `late_initcall`. Changes in v4: - Reworked the synchronization mechanism based on feedback from Palmer and Alexandre. - Instead of a post-hoc refresh, this version introduces a robust completion-based framework using an atomic counter to ensure async probes are finished before populating the vDSO. - Moved the vdso data initialization to a late_initcall to avoid impacting boot time. Changes in v3: - Retained existing blank line. Changes in v2: - Addressed feedback from Yixun's regarding #ifdef CONFIG_MMU usage. - Updated commit message to provide a high-level summary. - Added Fixes tag for commit e7c9d66e313b. v1: https://lore.kernel.org/linux-riscv/20250521052754.185231-1-wangjingwei@isc… arch/riscv/include/asm/hwprobe.h | 8 ++- arch/riscv/include/asm/vdso/arch_data.h | 6 ++ arch/riscv/kernel/sys_hwprobe.c | 71 ++++++++++++++++++---- arch/riscv/kernel/unaligned_access_speed.c | 9 ++- arch/riscv/kernel/vdso/hwprobe.c | 2 +- 5 files changed, 79 insertions(+), 17 deletions(-) diff --git a/arch/riscv/include/asm/hwprobe.h b/arch/riscv/include/asm/hwprobe.h index 7fe0a379474ae2c6..3b2888126e659ea1 100644 --- a/arch/riscv/include/asm/hwprobe.h +++ b/arch/riscv/include/asm/hwprobe.h @@ -40,5 +40,11 @@ static inline bool riscv_hwprobe_pair_cmp(struct riscv_hwprobe *pair, return pair->value == other_pair->value; } - +#ifdef CONFIG_MMU +void riscv_hwprobe_register_async_probe(void); +void riscv_hwprobe_complete_async_probe(void); +#else +static inline void riscv_hwprobe_register_async_probe(void) {} +static inline void riscv_hwprobe_complete_async_probe(void) {} +#endif #endif diff --git a/arch/riscv/include/asm/vdso/arch_data.h b/arch/riscv/include/asm/vdso/arch_data.h index da57a3786f7a53c8..88b37af55175129b 100644 --- a/arch/riscv/include/asm/vdso/arch_data.h +++ b/arch/riscv/include/asm/vdso/arch_data.h @@ -12,6 +12,12 @@ struct vdso_arch_data { /* Boolean indicating all CPUs have the same static hwprobe values. */ __u8 homogeneous_cpus; + + /* + * A gate to check and see if the hwprobe data is actually ready, as + * probing is deferred to avoid boot slowdowns. + */ + __u8 ready; }; #endif /* __RISCV_ASM_VDSO_ARCH_DATA_H */ diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c index 0b170e18a2beba57..fecb6790fa88e96c 100644 --- a/arch/riscv/kernel/sys_hwprobe.c +++ b/arch/riscv/kernel/sys_hwprobe.c @@ -5,6 +5,8 @@ * more details. */ #include <linux/syscalls.h> +#include <linux/completion.h> +#include <linux/atomic.h> #include <asm/cacheflush.h> #include <asm/cpufeature.h> #include <asm/hwprobe.h> @@ -452,28 +454,36 @@ static int hwprobe_get_cpus(struct riscv_hwprobe __user *pairs, return 0; } -static int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs, - size_t pair_count, size_t cpusetsize, - unsigned long __user *cpus_user, - unsigned int flags) -{ - if (flags & RISCV_HWPROBE_WHICH_CPUS) - return hwprobe_get_cpus(pairs, pair_count, cpusetsize, - cpus_user, flags); +#ifdef CONFIG_MMU - return hwprobe_get_values(pairs, pair_count, cpusetsize, - cpus_user, flags); +static DECLARE_COMPLETION(boot_probes_done); +static atomic_t pending_boot_probes = ATOMIC_INIT(1); + +void riscv_hwprobe_register_async_probe(void) +{ + atomic_inc(&pending_boot_probes); } -#ifdef CONFIG_MMU +void riscv_hwprobe_complete_async_probe(void) +{ + if (atomic_dec_and_test(&pending_boot_probes)) + complete(&boot_probes_done); +} -static int __init init_hwprobe_vdso_data(void) +static int complete_hwprobe_vdso_data(void) { struct vdso_arch_data *avd = vdso_k_arch_data; u64 id_bitsmash = 0; struct riscv_hwprobe pair; int key; + /* We've probably already produced these values. */ + if (likely(avd->ready)) + return 0; + + if (unlikely(!atomic_dec_and_test(&pending_boot_probes))) + wait_for_completion(&boot_probes_done); + /* * Initialize vDSO data with the answers for the "all CPUs" case, to * save a syscall in the common case. @@ -501,13 +511,48 @@ static int __init init_hwprobe_vdso_data(void) * vDSO should defer to the kernel for exotic cpu masks. */ avd->homogeneous_cpus = id_bitsmash != 0 && id_bitsmash != -1; + + /* + * Make sure all the VDSO values are visible before we look at them. + * This pairs with the implicit "no speculativly visible accesses" + * barrier in the VDSO hwprobe code. + */ + smp_wmb(); + avd->ready = true; + return 0; +} + +static int __init init_hwprobe_vdso_data(void) +{ + struct vdso_arch_data *avd = vdso_k_arch_data; + + /* + * Prevent the vDSO cached values from being used, as they're not ready + * yet. + */ + avd->ready = false; return 0; } -arch_initcall_sync(init_hwprobe_vdso_data); +late_initcall(init_hwprobe_vdso_data); #endif /* CONFIG_MMU */ +static int do_riscv_hwprobe(struct riscv_hwprobe __user *pairs, + size_t pair_count, size_t cpusetsize, + unsigned long __user *cpus_user, + unsigned int flags) +{ + complete_hwprobe_vdso_data(); + + if (flags & RISCV_HWPROBE_WHICH_CPUS) + return hwprobe_get_cpus(pairs, pair_count, cpusetsize, + cpus_user, flags); + + return hwprobe_get_values(pairs, pair_count, cpusetsize, + cpus_user, flags); +} + SYSCALL_DEFINE5(riscv_hwprobe, struct riscv_hwprobe __user *, pairs, size_t, pair_count, size_t, cpusetsize, unsigned long __user *, cpus, unsigned int, flags) diff --git a/arch/riscv/kernel/unaligned_access_speed.c b/arch/riscv/kernel/unaligned_access_speed.c index ae2068425fbcd207..4b8ad2673b0f7470 100644 --- a/arch/riscv/kernel/unaligned_access_speed.c +++ b/arch/riscv/kernel/unaligned_access_speed.c @@ -379,6 +379,7 @@ static void check_vector_unaligned_access(struct work_struct *work __always_unus static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused) { schedule_on_each_cpu(check_vector_unaligned_access); + riscv_hwprobe_complete_async_probe(); return 0; } @@ -473,8 +474,12 @@ static int __init check_unaligned_access_all_cpus(void) per_cpu(vector_misaligned_access, cpu) = unaligned_vector_speed_param; } else if (!check_vector_unaligned_access_emulated_all_cpus() && IS_ENABLED(CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS)) { - kthread_run(vec_check_unaligned_access_speed_all_cpus, - NULL, "vec_check_unaligned_access_speed_all_cpus"); + riscv_hwprobe_register_async_probe(); + if (IS_ERR(kthread_run(vec_check_unaligned_access_speed_all_cpus, + NULL, "vec_check_unaligned_access_speed_all_cpus"))) { + pr_warn("Failed to create vec_unalign_check kthread\n"); + riscv_hwprobe_complete_async_probe(); + } } /* diff --git a/arch/riscv/kernel/vdso/hwprobe.c b/arch/riscv/kernel/vdso/hwprobe.c index 2ddeba6c68dda09b..bf77b4c1d2d8e803 100644 --- a/arch/riscv/kernel/vdso/hwprobe.c +++ b/arch/riscv/kernel/vdso/hwprobe.c @@ -27,7 +27,7 @@ static int riscv_vdso_get_values(struct riscv_hwprobe *pairs, size_t pair_count, * homogeneous, then this function can handle requests for arbitrary * masks. */ - if ((flags != 0) || (!all_cpus && !avd->homogeneous_cpus)) + if ((flags != 0) || (!all_cpus && !avd->homogeneous_cpus) || unlikely(!avd->ready)) return riscv_hwprobe(pairs, pair_count, cpusetsize, cpus, flags); /* This is something we can handle, fill out the pairs. */ -- 2.50.1

1 week, 4 days

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[PATCH] amdgpu/amdgpu_discovery: increase timeout limit for IFWI init

by Xaver Hugl

With a timeout of only 1 second, my rx 5700XT fails to initialize, so this increases the timeout to 2s. Closes https://gitlab.freedesktop.org/drm/amd/-/issues/3697 Signed-off-by: Xaver Hugl <xaver.hugl(a)kde.org> Cc: stable(a)vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c index 6d34eac0539d..ae6908b57d78 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c @@ -275,7 +275,7 @@ static int amdgpu_discovery_read_binary_from_mem(struct amdgpu_device *adev, int i, ret = 0; if (!amdgpu_sriov_vf(adev)) { - /* It can take up to a second for IFWI init to complete on some dGPUs, + /* It can take up to two seconds for IFWI init to complete on some dGPUs, * but generally it should be in the 60-100ms range. Normally this starts * as soon as the device gets power so by the time the OS loads this has long * completed. However, when a card is hotplugged via e.g., USB4, we need to @@ -283,7 +283,7 @@ static int amdgpu_discovery_read_binary_from_mem(struct amdgpu_device *adev, * continue. */ - for (i = 0; i < 1000; i++) { + for (i = 0; i < 2000; i++) { msg = RREG32(mmMP0_SMN_C2PMSG_33); if (msg & 0x80000000) break; -- 2.50.1

1 week, 5 days

2
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[PATCH] eventpoll: Fix semi-unbounded recursion

by Jann Horn

Ensure that epoll instances can never form a graph deeper than EP_MAX_NESTS+1 links. Currently, ep_loop_check_proc() ensures that the graph is loop-free and does some recursion depth checks, but those recursion depth checks don't limit the depth of the resulting tree for two reasons: - They don't look upwards in the tree. - If there are multiple downwards paths of different lengths, only one of the paths is actually considered for the depth check since commit 28d82dc1c4ed ("epoll: limit paths"). Essentially, the current recursion depth check in ep_loop_check_proc() just serves to prevent it from recursing too deeply while checking for loops. A more thorough check is done in reverse_path_check() after the new graph edge has already been created; this checks, among other things, that no paths going upwards from any non-epoll file with a length of more than 5 edges exist. However, this check does not apply to non-epoll files. As a result, it is possible to recurse to a depth of at least roughly 500, tested on v6.15. (I am unsure if deeper recursion is possible; and this may have changed with commit 8c44dac8add7 ("eventpoll: Fix priority inversion problem").) To fix it: 1. In ep_loop_check_proc(), note the subtree depth of each visited node, and use subtree depths for the total depth calculation even when a subtree has already been visited. 2. Add ep_get_upwards_depth_proc() for similarly determining the maximum depth of an upwards walk. 3. In ep_loop_check(), use these values to limit the total path length between epoll nodes to EP_MAX_NESTS edges. Fixes: 22bacca48a17 ("epoll: prevent creating circular epoll structures") Cc: stable(a)vger.kernel.org Signed-off-by: Jann Horn <jannh(a)google.com> --- fs/eventpoll.c | 60 ++++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 46 insertions(+), 14 deletions(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index d4dbffdedd08..44648cc09250 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -218,6 +218,7 @@ struct eventpoll { /* used to optimize loop detection check */ u64 gen; struct hlist_head refs; + u8 loop_check_depth; /* * usage count, used together with epitem->dying to @@ -2142,23 +2143,24 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events, } /** - * ep_loop_check_proc - verify that adding an epoll file inside another - * epoll structure does not violate the constraints, in - * terms of closed loops, or too deep chains (which can - * result in excessive stack usage). + * ep_loop_check_proc - verify that adding an epoll file @ep inside another + * epoll file does not create closed loops, and + * determine the depth of the subtree starting at @ep * * @ep: the &struct eventpoll to be currently checked. * @depth: Current depth of the path being checked. * - * Return: %zero if adding the epoll @file inside current epoll - * structure @ep does not violate the constraints, or %-1 otherwise. + * Return: depth of the subtree, or INT_MAX if we found a loop or went too deep. */ static int ep_loop_check_proc(struct eventpoll *ep, int depth) { - int error = 0; + int result = 0; struct rb_node *rbp; struct epitem *epi; + if (ep->gen == loop_check_gen) + return ep->loop_check_depth; + mutex_lock_nested(&ep->mtx, depth + 1); ep->gen = loop_check_gen; for (rbp = rb_first_cached(&ep->rbr); rbp; rbp = rb_next(rbp)) { @@ -2166,13 +2168,11 @@ static int ep_loop_check_proc(struct eventpoll *ep, int depth) if (unlikely(is_file_epoll(epi->ffd.file))) { struct eventpoll *ep_tovisit; ep_tovisit = epi->ffd.file->private_data; - if (ep_tovisit->gen == loop_check_gen) - continue; if (ep_tovisit == inserting_into || depth > EP_MAX_NESTS) - error = -1; + result = INT_MAX; else - error = ep_loop_check_proc(ep_tovisit, depth + 1); - if (error != 0) + result = max(result, ep_loop_check_proc(ep_tovisit, depth + 1) + 1); + if (result > EP_MAX_NESTS) break; } else { /* @@ -2186,9 +2186,27 @@ static int ep_loop_check_proc(struct eventpoll *ep, int depth) list_file(epi->ffd.file); } } + ep->loop_check_depth = result; mutex_unlock(&ep->mtx); - return error; + return result; +} + +/** + * ep_get_upwards_depth_proc - determine depth of @ep when traversed upwards + */ +static int ep_get_upwards_depth_proc(struct eventpoll *ep, int depth) +{ + int result = 0; + struct epitem *epi; + + if (ep->gen == loop_check_gen) + return ep->loop_check_depth; + hlist_for_each_entry_rcu(epi, &ep->refs, fllink) + result = max(result, ep_get_upwards_depth_proc(epi->ep, depth + 1) + 1); + ep->gen = loop_check_gen; + ep->loop_check_depth = result; + return result; } /** @@ -2204,8 +2222,22 @@ static int ep_loop_check_proc(struct eventpoll *ep, int depth) */ static int ep_loop_check(struct eventpoll *ep, struct eventpoll *to) { + int depth, upwards_depth; + inserting_into = ep; - return ep_loop_check_proc(to, 0); + /* + * Check how deep down we can get from @to, and whether it is possible + * to loop up to @ep. + */ + depth = ep_loop_check_proc(to, 0); + if (depth > EP_MAX_NESTS) + return -1; + /* Check how far up we can go from @ep. */ + rcu_read_lock(); + upwards_depth = ep_get_upwards_depth_proc(ep, 0); + rcu_read_unlock(); + + return (depth+1+upwards_depth > EP_MAX_NESTS) ? -1 : 0; } static void clear_tfile_check_list(void) --- base-commit: 0ff41df1cb268fc69e703a08a57ee14ae967d0ca change-id: 20250711-epoll-recursion-fix-fb0e336b2aeb -- Jann Horn <jannh(a)google.com>

1 week, 5 days

2
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[PATCH 6.12] Drivers: hv: Make the sysfs node size for the ring buffer dynamic

by Naman Jain

The ring buffer size varies across VMBus channels. The size of sysfs node for the ring buffer is currently hardcoded to 4 MB. Userspace clients either use fstat() or hardcode this size for doing mmap(). To address this, make the sysfs node size dynamic to reflect the actual ring buffer size for each channel. This will ensure that fstat() on ring sysfs node always returns the correct size of ring buffer. This is a backport of the upstream commit 65995e97a1ca ("Drivers: hv: Make the sysfs node size for the ring buffer dynamic") with modifications, as the original patch has missing dependencies on kernel v6.12.x. The structure "struct attribute_group" does not have bin_size field in v6.12.x kernel so the logic of configuring size of sysfs node for ring buffer has been moved to vmbus_chan_bin_attr_is_visible(). Original change was not a fix, but it needs to be backported to fix size related discrepancy caused by the commit mentioned in Fixes tag. Fixes: bf1299797c3c ("uio_hv_generic: Align ring size to system page") Cc: <stable(a)vger.kernel.org> # 6.12.x Signed-off-by: Naman Jain <namjain(a)linux.microsoft.com> --- This change won't apply on older kernels currently due to missing dependencies. I will take care of them after this goes in. I did not retain any Reviewed-by or Tested-by tags, since the code has changed completely, while the functionality remains same. Requesting Michael, Dexuan, Wei to please review again. --- drivers/hv/vmbus_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 1f519e925f06..616e63fb2f15 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1810,7 +1810,6 @@ static struct bin_attribute chan_attr_ring_buffer = { .name = "ring", .mode = 0600, }, - .size = 2 * SZ_2M, .mmap = hv_mmap_ring_buffer_wrapper, }; static struct attribute *vmbus_chan_attrs[] = { @@ -1866,6 +1865,7 @@ static umode_t vmbus_chan_bin_attr_is_visible(struct kobject *kobj, /* Hide ring attribute if channel's ring_sysfs_visible is set to false */ if (attr == &chan_attr_ring_buffer && !channel->ring_sysfs_visible) return 0; + attr->size = channel->ringbuffer_pagecount << PAGE_SHIFT; return attr->attr.mode; } -- 2.34.1

1 week, 5 days

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[PATCH RESEND] drm: Fix potential null pointer dereference issues in drm_managed.c

by Haoxiang Li

Add check for the return value of kstrdup_const() in drm_managed.c to prevent potential null pointer dereference. Fixes: c6603c740e0e ("drm: add managed resources tied to drm_device") Cc: stable(a)vger.kernel.org Signed-off-by: Haoxiang Li <haoxiang_li2024(a)163.com> --- drivers/gpu/drm/drm_managed.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/gpu/drm/drm_managed.c b/drivers/gpu/drm/drm_managed.c index cc4c463daae7..368763d4c24e 100644 --- a/drivers/gpu/drm/drm_managed.c +++ b/drivers/gpu/drm/drm_managed.c @@ -151,6 +151,11 @@ int __drmm_add_action(struct drm_device *dev, } dr->node.name = kstrdup_const(name, GFP_KERNEL); + if (!dr->node.name) { + kfree(dr); + return -ENOMEM; + } + if (data) { void_ptr = (void **)&dr->data; *void_ptr = data; @@ -236,6 +241,10 @@ void *drmm_kmalloc(struct drm_device *dev, size_t size, gfp_t gfp) return NULL; } dr->node.name = kstrdup_const("kmalloc", gfp); + if (dr->node.name) { + kfree(dr); + return NULL; + } add_dr(dev, dr); -- 2.25.1

1 week, 6 days

3
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[PATCH v4] gpio-mlxbf2: use platform_get_irq_optional()

by David Thompson

The gpio-mlxbf2 driver interfaces with four GPIO controllers, device instances 0-3. There are two IRQ resources shared between the four controllers, and they are found in the ACPI table for instances 0 and 3. The driver should not use platform_get_irq(), otherwise this error is logged when probing instances 1 and 2: mlxbf2_gpio MLNXBF22:01: error -ENXIO: IRQ index 0 not found Fixes: 2b725265cb08 ("gpio: mlxbf2: Introduce IRQ support") Cc: stable(a)vger.kernel.org Signed-off-by: David Thompson <davthompson(a)nvidia.com> Reviewed-by: Shravan Kumar Ramani <shravankr(a)nvidia.com> --- v4: updated logic to simply use platform_get_irq_optional() v3: added version history v2: added tag "Cc: stable(a)vger.kernel.org" drivers/gpio/gpio-mlxbf2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c index 6f3dda6b635f..390f2e74a9d8 100644 --- a/drivers/gpio/gpio-mlxbf2.c +++ b/drivers/gpio/gpio-mlxbf2.c @@ -397,7 +397,7 @@ mlxbf2_gpio_probe(struct platform_device *pdev) gc->ngpio = npins; gc->owner = THIS_MODULE; - irq = platform_get_irq(pdev, 0); + irq = platform_get_irq_optional(pdev, 0); if (irq >= 0) { girq = &gs->gc.irq; gpio_irq_chip_set_chip(girq, &mlxbf2_gpio_irq_chip); -- 2.43.2

1 week, 6 days

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[PATCH] firmware: meson_sm: fix device leak at probe

by Johan Hovold

Make sure to drop the reference to the secure monitor device taken by of_find_device_by_node() when looking up its driver data on behalf of other drivers (e.g. during probe). Note that holding a reference to the platform device does not prevent its driver data from going away so there is no point in keeping the reference after the helper returns. Fixes: 8cde3c2153e8 ("firmware: meson_sm: Rework driver as a proper platform driver") Cc: stable(a)vger.kernel.org # 5.5 Cc: Carlo Caione <ccaione(a)baylibre.com> Signed-off-by: Johan Hovold <johan(a)kernel.org> --- drivers/firmware/meson/meson_sm.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c index f25a9746249b..3ab67aaa9e5d 100644 --- a/drivers/firmware/meson/meson_sm.c +++ b/drivers/firmware/meson/meson_sm.c @@ -232,11 +232,16 @@ EXPORT_SYMBOL(meson_sm_call_write); struct meson_sm_firmware *meson_sm_get(struct device_node *sm_node) { struct platform_device *pdev = of_find_device_by_node(sm_node); + struct meson_sm_firmware *fw; if (!pdev) return NULL; - return platform_get_drvdata(pdev); + fw = platform_get_drvdata(pdev); + + put_device(&pdev->dev); + + return fw; } EXPORT_SYMBOL_GPL(meson_sm_get); -- 2.49.1

1 week, 6 days

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[PATCH] usb: renesas-xhci: Fix External ROM access timeouts

by Marek Vasut

Increase the External ROM access timeouts to prevent failures during programming of External SPI EEPROM chips. The current timeouts are too short for some SPI EEPROMs used with uPD720201 controllers. The current timeout for Chip Erase in renesas_rom_erase() is 100 ms , the current timeout for Sector Erase issued by the controller before Page Program in renesas_fw_download_image() is also 100 ms. Neither timeout is sufficient for e.g. the Macronix MX25L5121E or MX25V5126F. MX25L5121E reference manual [1] page 35 section "ERASE AND PROGRAMMING PERFORMANCE" and page 23 section "Table 8. AC CHARACTERISTICS (Temperature = 0°C to 70°C for Commercial grade, VCC = 2.7V ~ 3.6V)" row "tCE" indicate that the maximum time required for Chip Erase opcode to complete is 2 s, and for Sector Erase it is 300 ms . MX25V5126F reference manual [2] page 47 section "13. ERASE AND PROGRAMMING PERFORMANCE (2.3V - 3.6V)" and page 42 section "Table 8. AC CHARACTERISTICS (Temperature = -40°C to 85°C for Industrial grade, VCC = 2.3V - 3.6V)" row "tCE" indicate that the maximum time required for Chip Erase opcode to complete is 3.2 s, and for Sector Erase it is 400 ms . Update the timeouts such, that Chip Erase timeout is set to 5 seconds, and Sector Erase timeout is set to 500 ms. Such lengthy timeouts ought to be sufficient for majority of SPI EEPROM chips. [1] https://www.macronix.com/Lists/Datasheet/Attachments/8634/MX25L5121E,%203V,… [2] https://www.macronix.com/Lists/Datasheet/Attachments/8750/MX25V5126F,%202.5… Fixes: 2478be82de44 ("usb: renesas-xhci: Add ROM loader for uPD720201") Signed-off-by: Marek Vasut <marek.vasut+renesas(a)mailbox.org> --- Cc: Geert Uytterhoeven <geert+renesas(a)glider.be> Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Cc: Mathias Nyman <mathias.nyman(a)intel.com> Cc: Vinod Koul <vkoul(a)kernel.org> Cc: <stable(a)vger.kernel.org> Cc: linux-renesas-soc(a)vger.kernel.org Cc: linux-usb(a)vger.kernel.org --- drivers/usb/host/xhci-pci-renesas.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/usb/host/xhci-pci-renesas.c b/drivers/usb/host/xhci-pci-renesas.c index 620f8f0febb8..86df80399c9f 100644 --- a/drivers/usb/host/xhci-pci-renesas.c +++ b/drivers/usb/host/xhci-pci-renesas.c @@ -47,8 +47,9 @@ #define RENESAS_ROM_ERASE_MAGIC 0x5A65726F #define RENESAS_ROM_WRITE_MAGIC 0x53524F4D -#define RENESAS_RETRY 10000 -#define RENESAS_DELAY 10 +#define RENESAS_RETRY 50000 /* 50000 * RENESAS_DELAY ~= 500ms */ +#define RENESAS_CHIP_ERASE_RETRY 500000 /* 500000 * RENESAS_DELAY ~= 5s */ +#define RENESAS_DELAY 10 #define RENESAS_FW_NAME "renesas_usb_fw.mem" @@ -407,7 +408,7 @@ static void renesas_rom_erase(struct pci_dev *pdev) /* sleep a bit while ROM is erased */ msleep(20); - for (i = 0; i < RENESAS_RETRY; i++) { + for (i = 0; i < RENESAS_CHIP_ERASE_RETRY; i++) { retval = pci_read_config_byte(pdev, RENESAS_ROM_STATUS, &status); status &= RENESAS_ROM_STATUS_ERASE; -- 2.47.2

2 weeks

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Text mode VGA-console scrolling is broken in upstream & stable trees

by Jari Ruusu

The patch that broke text mode VGA-console scrolling is this one: "vgacon: Add check for vc_origin address range in vgacon_scroll()" commit 864f9963ec6b4b76d104d595ba28110b87158003 upstream. How to preproduce: (1) boot a kernel that is configured to use text mode VGA-console (2) type commands: ls -l /usr/bin | less -S (3) scroll up/down with cursor-down/up keys Above mentioned patch seems to have landed in upstream and all kernel.org stable trees with zero testing. Even minimal testing would have shown that it breaks text mode VGA-console scrolling. Greg, Sasha, Linus, Please consider reverting that buggy patch from all affected trees. -- Jari Ruusu 4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD ACDF F073 3C80 8132 F189

2 weeks

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