February 2018 - Linux-stable-mirror

[Linux-stable-mirror] [PATCH] drm/i915/breadcrumbs: Ignore unsubmitted signalers

by Chris Wilson

When a request is preempted, it is unsubmitted from the HW queue and removed from the active list of breadcrumbs. In the process, this however triggers the signaler and it may see the clear rbtree with the old, and still valid, seqno, or it may match the cleared seqno with the now zero rq->global_seqno. This confuses the signaler into action and signaling the fence. Fixes: d6a2289d9d6b ("drm/i915: Remove the preempted request from the execution queue") Signed-off-by: Chris Wilson <chris(a)chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin(a)linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen(a)linux.intel.com> Cc: <stable(a)vger.kernel.org> # v4.12+ Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin(a)intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180206094633.30181-1-chris@… (cherry picked from commit fd10e2ce9905030d922e179a8047a4d50daffd8e) --- drivers/gpu/drm/i915/intel_breadcrumbs.c | 29 ++++++++++------------------- 1 file changed, 10 insertions(+), 19 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c index bd40fea16b4f..f54ddda9fdad 100644 --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c @@ -594,29 +594,16 @@ void intel_engine_remove_wait(struct intel_engine_cs *engine, spin_unlock_irq(&b->rb_lock); } -static bool signal_valid(const struct drm_i915_gem_request *request) -{ - return intel_wait_check_request(&request->signaling.wait, request); -} - static bool signal_complete(const struct drm_i915_gem_request *request) { if (!request) return false; - /* If another process served as the bottom-half it may have already - * signalled that this wait is already completed. - */ - if (intel_wait_complete(&request->signaling.wait)) - return signal_valid(request); - - /* Carefully check if the request is complete, giving time for the + /* + * Carefully check if the request is complete, giving time for the * seqno to be visible or if the GPU hung. */ - if (__i915_request_irq_complete(request)) - return true; - - return false; + return __i915_request_irq_complete(request); } static struct drm_i915_gem_request *to_signaler(struct rb_node *rb) @@ -659,9 +646,13 @@ static int intel_breadcrumbs_signaler(void *arg) request = i915_gem_request_get_rcu(request); rcu_read_unlock(); if (signal_complete(request)) { - local_bh_disable(); - dma_fence_signal(&request->fence); - local_bh_enable(); /* kick start the tasklets */ + if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, + &request->fence.flags)) { + local_bh_disable(); + dma_fence_signal(&request->fence); + GEM_BUG_ON(!i915_gem_request_completed(request)); + local_bh_enable(); /* kick start the tasklets */ + } spin_lock_irq(&b->rb_lock); -- 2.16.1

6 years, 11 months

2
1
0 0

[PATCH] xtensa: fix high memory/reserved memory collision

by Max Filippov

Xtensa memory initialization code frees high memory pages without checking whether they are in the reserved memory regions or not. That results in invalid value of totalram_pages and duplicate page usage by CMA and highmem. It produces a bunch of BUGs at startup looking like this: BUG: Bad page state in process swapper pfn:70800 page:be60c000 count:0 mapcount:-127 mapping: (null) index:0x1 flags: 0x80000000() raw: 80000000 00000000 00000001 ffffff80 00000000 be60c014 be60c014 0000000a page dumped because: nonzero mapcount Modules linked in: CPU: 0 PID: 1 Comm: swapper Tainted: G B 4.16.0-rc1-00015-g7928b2cbe55b-dirty #23 Stack: bd839d33 00000000 00000018 ba97b64c a106578c bd839d70 be60c000 00000000 a1378054 bd86a000 00000003 ba97b64c a1066166 bd839da0 be60c000 ffe00000 a1066b58 bd839dc0 be504000 00000000 000002f4 bd838000 00000000 0000001e Call Trace: [<a1065734>] bad_page+0xac/0xd0 [<a106578c>] free_pages_check_bad+0x34/0x4c [<a1066166>] __free_pages_ok+0xae/0x14c [<a1066b58>] __free_pages+0x30/0x64 [<a1365de5>] init_cma_reserved_pageblock+0x35/0x44 [<a13682dc>] cma_init_reserved_areas+0xf4/0x148 [<a10034b8>] do_one_initcall+0x80/0xf8 [<a1361c16>] kernel_init_freeable+0xda/0x13c [<a125b59d>] kernel_init+0x9/0xd0 [<a1004304>] ret_from_kernel_thread+0xc/0x18 Only free high memory pages that are not reserved. Cc: stable(a)vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc(a)gmail.com> --- arch/xtensa/mm/init.c | 70 +++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 63 insertions(+), 7 deletions(-) diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c index d776ec0d7b22..34aead7dcb48 100644 --- a/arch/xtensa/mm/init.c +++ b/arch/xtensa/mm/init.c @@ -79,19 +79,75 @@ void __init zones_init(void) free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); } +#ifdef CONFIG_HIGHMEM +static void __init free_area_high(unsigned long pfn, unsigned long end) +{ + for (; pfn < end; pfn++) + free_highmem_page(pfn_to_page(pfn)); +} + +static void __init free_highpages(void) +{ + unsigned long max_low = max_low_pfn; + struct memblock_region *mem, *res; + + reset_all_zones_managed_pages(); + /* set highmem page free */ + for_each_memblock(memory, mem) { + unsigned long start = memblock_region_memory_base_pfn(mem); + unsigned long end = memblock_region_memory_end_pfn(mem); + + /* Ignore complete lowmem entries */ + if (end <= max_low) + continue; + + if (memblock_is_nomap(mem)) + continue; + + /* Truncate partial highmem entries */ + if (start < max_low) + start = max_low; + + /* Find and exclude any reserved regions */ + for_each_memblock(reserved, res) { + unsigned long res_start, res_end; + + res_start = memblock_region_reserved_base_pfn(res); + res_end = memblock_region_reserved_end_pfn(res); + + if (res_end < start) + continue; + if (res_start < start) + res_start = start; + if (res_start > end) + res_start = end; + if (res_end > end) + res_end = end; + if (res_start != start) + free_area_high(start, res_start); + start = res_end; + if (start == end) + break; + } + + /* And now free anything which remains */ + if (start < end) + free_area_high(start, end); + } +} +#else +static void __init free_highpages(void) +{ +} +#endif + /* * Initialize memory pages. */ void __init mem_init(void) { -#ifdef CONFIG_HIGHMEM - unsigned long tmp; - - reset_all_zones_managed_pages(); - for (tmp = max_low_pfn; tmp < max_pfn; tmp++) - free_highmem_page(pfn_to_page(tmp)); -#endif + free_highpages(); max_mapnr = max_pfn - ARCH_PFN_OFFSET; high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT); -- 2.1.4

6 years, 11 months

1
0
0 0

[PATCH v3] platform/x86: dell-laptop: fix kbd_get_state's request value

by Laszlo Toth

Commit 9862b43624a5 ("platform/x86: dell-laptop: Allocate buffer on heap rather than globally") broke one request, changed it back to the original value. Tested on a Dell E6540, backlight came back. Fixes: 9862b43624a5 ("platform/x86: dell-laptop: Allocate buffer on heap rather than globally") Signed-off-by: Laszlo Toth <laszlth(a)gmail.com> --- Changes in v2: - split the fix and the function merge part Changes in v3: - added fixes tag drivers/platform/x86/dell-laptop.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c index 2a68f59..a37cff9 100644 --- a/drivers/platform/x86/dell-laptop.c +++ b/drivers/platform/x86/dell-laptop.c @@ -1279,7 +1279,7 @@ static int kbd_get_state(struct kbd_state *state) struct calling_interface_buffer buffer; int ret; - dell_fill_request(&buffer, 0, 0, 0, 0); + dell_fill_request(&buffer, 0x1, 0, 0, 0); ret = dell_send_request(&buffer, CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT); if (ret) -- 2.7.4

6 years, 11 months

1
0
0 0

[PATCH] nvme-pci: Remap CMB SQ entries on every controller reset

by Keith Busch

The controller memory buffer is remapped into a kernel address on each reset, but the driver was setting the submission queue base address only on the very first queue creation. The remapped address is likely to change after a reset, so accessing the old address will hit a kernel bug. This patch will set a CMB SQ base address each time the queue is created rather. Fixes: f63572dff1421 ("nvme: unmap CMB and remove sysfs file in reset path") Cc: Jon Derrick <jonathan.derrick(a)intel.com> Cc: <stable(a)vger.kernel.org> # 4.9+ Signed-off-by: Keith Busch <keith.busch(a)intel.com> --- drivers/nvme/host/pci.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 6fe7af00a1f4..e0f5153cd6ca 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1364,18 +1364,14 @@ static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues, static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq, int qid, int depth) { - if (qid && dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) { - unsigned offset = (qid - 1) * roundup(SQ_SIZE(depth), - dev->ctrl.page_size); - nvmeq->sq_dma_addr = dev->cmb_bus_addr + offset; - nvmeq->sq_cmds_io = dev->cmb + offset; - } else { - nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth), - &nvmeq->sq_dma_addr, GFP_KERNEL); - if (!nvmeq->sq_cmds) - return -ENOMEM; - } + /* CMB SQEs will be mapped before creation */ + if (qid && dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) + return 0; + nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth), + &nvmeq->sq_dma_addr, GFP_KERNEL); + if (!nvmeq->sq_cmds) + return -ENOMEM; return 0; } @@ -1449,6 +1445,13 @@ static int nvme_create_queue(struct nvme_queue *nvmeq, int qid) struct nvme_dev *dev = nvmeq->dev; int result; + if (dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) { + unsigned offset = (qid - 1) * roundup(SQ_SIZE(nvmeq->q_depth), + dev->ctrl.page_size); + nvmeq->sq_dma_addr = dev->cmb_bus_addr + offset; + nvmeq->sq_cmds_io = dev->cmb + offset; + } + nvmeq->cq_vector = qid - 1; result = adapter_alloc_cq(dev, qid, nvmeq); if (result < 0) -- 2.14.3

6 years, 11 months

1
0
0 0

[Linux-stable-mirror] [PATCH] uapi/if_ether.h: move __UAPI_DEF_ETHHDR libc define

by Hauke Mehrtens

This fixes a compile problem of some user space applications by not including linux/libc-compat.h in uapi/if_ether.h. linux/libc-compat.h checks which "features" the header files, included from the libc, provide to make the Linux kernel uapi header files only provide no conflicting structures and enums. If a user application mixes kernel headers and libc headers it could happen that linux/libc-compat.h gets included too early where not all other libc headers are included yet. Then the linux/libc-compat.h would not prevent all the redefinitions and we run into compile problems. This patch removes the include of linux/libc-compat.h from uapi/if_ether.h to fix the recently introduced case, but not all as this is more or less impossible. It is no problem to do the check directly in the if_ether.h file and not in libc-compat.h as this does not need any fancy glibc header detection as glibc never provided struct ethhdr and should define __UAPI_DEF_ETHHDR by them self when they will provide this. The following test program did not compile correctly any more: int main(void) { return 0; } Fixes: 6926e041a892 ("uapi/if_ether.h: prevent redefinition of struct ethhdr") Reported-by: Guillaume Nault <g.nault(a)alphalink.fr> Cc: <stable(a)vger.kernel.org> # 4.15 Signed-off-by: Hauke Mehrtens <hauke(a)hauke-m.de> --- include/uapi/linux/if_ether.h | 6 +++++- include/uapi/linux/libc-compat.h | 6 ------ 2 files changed, 5 insertions(+), 7 deletions(-) diff --git a/include/uapi/linux/if_ether.h b/include/uapi/linux/if_ether.h index f8cb5760ea4f..8bbbcb5cd94b 100644 --- a/include/uapi/linux/if_ether.h +++ b/include/uapi/linux/if_ether.h @@ -23,7 +23,6 @@ #define _UAPI_LINUX_IF_ETHER_H #include <linux/types.h> -#include <linux/libc-compat.h> /* * IEEE 802.3 Ethernet magic constants. The frame sizes omit the preamble @@ -151,6 +150,11 @@ * This is an Ethernet frame header. */ +/* allow libcs like musl to deactivate this, glibc does not implement this. */ +#ifndef __UAPI_DEF_ETHHDR +#define __UAPI_DEF_ETHHDR 1 +#endif + #if __UAPI_DEF_ETHHDR struct ethhdr { unsigned char h_dest[ETH_ALEN]; /* destination eth addr */ diff --git a/include/uapi/linux/libc-compat.h b/include/uapi/linux/libc-compat.h index fc29efaa918c..8254c937c9f4 100644 --- a/include/uapi/linux/libc-compat.h +++ b/include/uapi/linux/libc-compat.h @@ -264,10 +264,4 @@ #endif /* __GLIBC__ */ -/* Definitions for if_ether.h */ -/* allow libcs like musl to deactivate this, glibc does not implement this. */ -#ifndef __UAPI_DEF_ETHHDR -#define __UAPI_DEF_ETHHDR 1 -#endif - #endif /* _UAPI_LIBC_COMPAT_H */ -- 2.11.0

6 years, 11 months

3
3
0 0

v4.9.81 build: 0 failures 0 warnings (v4.9.81)

by Build bot for Mark Brown

Tree/Branch: v4.9.81 Git describe: v4.9.81 Commit: 7f3bd8db99 Linux 4.9.81 Build Time: 92 min 38 sec Passed: 10 / 10 (100.00 %) Failed: 0 / 10 ( 0.00 %) Errors: 0 Warnings: 0 Section Mismatches: 0 ------------------------------------------------------------------------------- defconfigs with issues (other than build errors): ------------------------------------------------------------------------------- =============================================================================== Detailed per-defconfig build reports below: ------------------------------------------------------------------------------- Passed with no errors, warnings or mismatches: arm64-allnoconfig arm64-allmodconfig arm-multi_v5_defconfig arm-multi_v7_defconfig x86_64-defconfig arm-allmodconfig arm-allnoconfig x86_64-allnoconfig arm-multi_v4t_defconfig arm64-defconfig close failed in file object destructor: sys.excepthook is missing lost sys.stderr

6 years, 11 months

1
0
0 0

Patch "usb: gadget: uvc: Missing files for configfs interface" has been added to the 4.4-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled usb: gadget: uvc: Missing files for configfs interface to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: usb-gadget-uvc-missing-files-for-configfs-interface.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From c8cd751060b149997b9de53a494fb1490ded72c5 Mon Sep 17 00:00:00 2001 From: Petr Cvek <petr.cvek(a)tul.cz> Date: Tue, 7 Mar 2017 00:57:20 +0100 Subject: usb: gadget: uvc: Missing files for configfs interface From: Petr Cvek <petr.cvek(a)tul.cz> commit c8cd751060b149997b9de53a494fb1490ded72c5 upstream. Commit 76e0da34c7ce ("usb-gadget/uvc: use per-attribute show and store methods") caused a stringification of an undefined macro argument "aname", so three UVC parameters (streaming_interval, streaming_maxpacket and streaming_maxburst) were named "aname". Add the definition of "aname" to the main macro and name the filenames as originaly intended. Signed-off-by: Petr Cvek <petr.cvek(a)tul.cz> Signed-off-by: Felipe Balbi <felipe.balbi(a)linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- drivers/usb/gadget/function/uvc_configfs.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) --- a/drivers/usb/gadget/function/uvc_configfs.c +++ b/drivers/usb/gadget/function/uvc_configfs.c @@ -2202,7 +2202,7 @@ static struct configfs_item_operations u .release = uvc_attr_release, }; -#define UVCG_OPTS_ATTR(cname, conv, str2u, uxx, vnoc, limit) \ +#define UVCG_OPTS_ATTR(cname, aname, conv, str2u, uxx, vnoc, limit) \ static ssize_t f_uvc_opts_##cname##_show( \ struct config_item *item, char *page) \ { \ @@ -2245,16 +2245,16 @@ end: \ return ret; \ } \ \ -UVC_ATTR(f_uvc_opts_, cname, aname) +UVC_ATTR(f_uvc_opts_, cname, cname) #define identity_conv(x) (x) -UVCG_OPTS_ATTR(streaming_interval, identity_conv, kstrtou8, u8, identity_conv, - 16); -UVCG_OPTS_ATTR(streaming_maxpacket, le16_to_cpu, kstrtou16, u16, le16_to_cpu, - 3072); -UVCG_OPTS_ATTR(streaming_maxburst, identity_conv, kstrtou8, u8, identity_conv, - 15); +UVCG_OPTS_ATTR(streaming_interval, streaming_interval, identity_conv, + kstrtou8, u8, identity_conv, 16); +UVCG_OPTS_ATTR(streaming_maxpacket, streaming_maxpacket, le16_to_cpu, + kstrtou16, u16, le16_to_cpu, 3072); +UVCG_OPTS_ATTR(streaming_maxburst, streaming_maxburst, identity_conv, + kstrtou8, u8, identity_conv, 15); #undef identity_conv Patches currently in stable-queue which might be from petr.cvek(a)tul.cz are queue-4.4/usb-gadget-uvc-missing-files-for-configfs-interface.patch

6 years, 11 months

1
0
0 0

[Linux-stable-mirror] [PATCH 4.4] x86/kaiser: fix build error with KASAN && !FUNCTION_GRAPH_TRACER

by Eric Biggers

This is a build fix for the 4.4 PTI backport. 4.4 kernels do not have commit be7635e7287e ("arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections") which went into 4.6. Consequently, the irqentry sections are only created when CONFIG_FUNCTION_GRAPH_TRACER is enabled, not also when CONFIG_KASAN is enabled. Therefore, fix the condition for trying to add a user mapping for this section. This fixes the following build error: arch/x86/mm/kaiser.c: In function ‘kaiser_init’: arch/x86/mm/kaiser.c:367:33: error: ‘__irqentry_text_start’ undeclared (first use in this function) kaiser_add_user_map_ptrs_early(__irqentry_text_start, [...] Signed-off-by: Eric Biggers <ebiggers(a)google.com> --- arch/x86/mm/kaiser.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/mm/kaiser.c b/arch/x86/mm/kaiser.c index 2298434f7bdb..7a72e32e4806 100644 --- a/arch/x86/mm/kaiser.c +++ b/arch/x86/mm/kaiser.c @@ -363,7 +363,7 @@ void __init kaiser_init(void) kaiser_add_user_map_ptrs_early(__entry_text_start, __entry_text_end, __PAGE_KERNEL_RX); -#if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN) +#ifdef CONFIG_FUNCTION_GRAPH_TRACER kaiser_add_user_map_ptrs_early(__irqentry_text_start, __irqentry_text_end, __PAGE_KERNEL_RX); -- 2.16.0.rc1.238.g530d649a79-goog

6 years, 11 months

4
3
0 0

Patch "sched/rt: Use container_of() to get root domain in rto_push_irq_work_func()" has been added to the 4.4-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled sched/rt: Use container_of() to get root domain in rto_push_irq_work_func() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: sched-rt-use-container_of-to-get-root-domain-in-rto_push_irq_work_func.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From ad0f1d9d65938aec72a698116cd73a980916895e Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" <rostedt(a)goodmis.org> Date: Tue, 23 Jan 2018 20:45:37 -0500 Subject: sched/rt: Use container_of() to get root domain in rto_push_irq_work_func() From: Steven Rostedt (VMware) <rostedt(a)goodmis.org> commit ad0f1d9d65938aec72a698116cd73a980916895e upstream. When the rto_push_irq_work_func() is called, it looks at the RT overloaded bitmask in the root domain via the runqueue (rq->rd). The problem is that during CPU up and down, nothing here stops rq->rd from changing between taking the rq->rd->rto_lock and releasing it. That means the lock that is released is not the same lock that was taken. Instead of using this_rq()->rd to get the root domain, as the irq work is part of the root domain, we can simply get the root domain from the irq work that is passed to the routine: container_of(work, struct root_domain, rto_push_work) This keeps the root domain consistent. Reported-by: Pavan Kondeti <pkondeti(a)codeaurora.org> Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> Cc: Andrew Morton <akpm(a)linux-foundation.org> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Mike Galbraith <efault(a)gmx.de> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Fixes: 4bdced5c9a292 ("sched/rt: Simplify the IPI based RT balancing logic") Link: http://lkml.kernel.org/r/CAEU1=PkiHO35Dzna8EQqNSKW1fr1y1zRQ5y66X117MG06sQtN… Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- kernel/sched/rt.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1833,9 +1833,8 @@ static void push_rt_tasks(struct rq *rq) * the rt_loop_next will cause the iterator to perform another scan. * */ -static int rto_next_cpu(struct rq *rq) +static int rto_next_cpu(struct root_domain *rd) { - struct root_domain *rd = rq->rd; int next; int cpu; @@ -1911,7 +1910,7 @@ static void tell_cpu_to_push(struct rq * * Otherwise it is finishing up and an ipi needs to be sent. */ if (rq->rd->rto_cpu < 0) - cpu = rto_next_cpu(rq); + cpu = rto_next_cpu(rq->rd); raw_spin_unlock(&rq->rd->rto_lock); @@ -1924,6 +1923,8 @@ static void tell_cpu_to_push(struct rq * /* Called from hardirq context */ void rto_push_irq_work_func(struct irq_work *work) { + struct root_domain *rd = + container_of(work, struct root_domain, rto_push_work); struct rq *rq; int cpu; @@ -1939,18 +1940,18 @@ void rto_push_irq_work_func(struct irq_w raw_spin_unlock(&rq->lock); } - raw_spin_lock(&rq->rd->rto_lock); + raw_spin_lock(&rd->rto_lock); /* Pass the IPI to the next rt overloaded queue */ - cpu = rto_next_cpu(rq); + cpu = rto_next_cpu(rd); - raw_spin_unlock(&rq->rd->rto_lock); + raw_spin_unlock(&rd->rto_lock); if (cpu < 0) return; /* Try the next RT overloaded CPU */ - irq_work_queue_on(&rq->rd->rto_push_work, cpu); + irq_work_queue_on(&rd->rto_push_work, cpu); } #endif /* HAVE_RT_PUSH_IPI */ Patches currently in stable-queue which might be from rostedt(a)goodmis.org are queue-4.4/sched-rt-use-container_of-to-get-root-domain-in-rto_push_irq_work_func.patch queue-4.4/sched-rt-up-the-root-domain-ref-count-when-passing-it-around-via-ipis.patch

6 years, 11 months

1
0
0 0

Patch "sched/rt: Up the root domain ref count when passing it around via IPIs" has been added to the 4.4-stable tree

by gregkh＠linuxfoundation.org

This is a note to let you know that I've just added the patch titled sched/rt: Up the root domain ref count when passing it around via IPIs to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum… The filename of the patch is: sched-rt-up-the-root-domain-ref-count-when-passing-it-around-via-ipis.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable(a)vger.kernel.org> know about it. >From 364f56653708ba8bcdefd4f0da2a42904baa8eeb Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" <rostedt(a)goodmis.org> Date: Tue, 23 Jan 2018 20:45:38 -0500 Subject: sched/rt: Up the root domain ref count when passing it around via IPIs From: Steven Rostedt (VMware) <rostedt(a)goodmis.org> commit 364f56653708ba8bcdefd4f0da2a42904baa8eeb upstream. When issuing an IPI RT push, where an IPI is sent to each CPU that has more than one RT task scheduled on it, it references the root domain's rto_mask, that contains all the CPUs within the root domain that has more than one RT task in the runable state. The problem is, after the IPIs are initiated, the rq->lock is released. This means that the root domain that is associated to the run queue could be freed while the IPIs are going around. Add a sched_get_rd() and a sched_put_rd() that will increment and decrement the root domain's ref count respectively. This way when initiating the IPIs, the scheduler will up the root domain's ref count before releasing the rq->lock, ensuring that the root domain does not go away until the IPI round is complete. Reported-by: Pavan Kondeti <pkondeti(a)codeaurora.org> Signed-off-by: Steven Rostedt (VMware) <rostedt(a)goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> Cc: Andrew Morton <akpm(a)linux-foundation.org> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Mike Galbraith <efault(a)gmx.de> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Thomas Gleixner <tglx(a)linutronix.de> Fixes: 4bdced5c9a292 ("sched/rt: Simplify the IPI based RT balancing logic") Link: http://lkml.kernel.org/r/CAEU1=PkiHO35Dzna8EQqNSKW1fr1y1zRQ5y66X117MG06sQtN… Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> --- kernel/sched/core.c | 13 +++++++++++++ kernel/sched/rt.c | 9 +++++++-- kernel/sched/sched.h | 2 ++ 3 files changed, 22 insertions(+), 2 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5896,6 +5896,19 @@ static void rq_attach_root(struct rq *rq call_rcu_sched(&old_rd->rcu, free_rootdomain); } +void sched_get_rd(struct root_domain *rd) +{ + atomic_inc(&rd->refcount); +} + +void sched_put_rd(struct root_domain *rd) +{ + if (!atomic_dec_and_test(&rd->refcount)) + return; + + call_rcu_sched(&rd->rcu, free_rootdomain); +} + static int init_rootdomain(struct root_domain *rd) { memset(rd, 0, sizeof(*rd)); --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1916,8 +1916,11 @@ static void tell_cpu_to_push(struct rq * rto_start_unlock(&rq->rd->rto_loop_start); - if (cpu >= 0) + if (cpu >= 0) { + /* Make sure the rd does not get freed while pushing */ + sched_get_rd(rq->rd); irq_work_queue_on(&rq->rd->rto_push_work, cpu); + } } /* Called from hardirq context */ @@ -1947,8 +1950,10 @@ void rto_push_irq_work_func(struct irq_w raw_spin_unlock(&rd->rto_lock); - if (cpu < 0) + if (cpu < 0) { + sched_put_rd(rd); return; + } /* Try the next RT overloaded CPU */ irq_work_queue_on(&rd->rto_push_work, cpu); --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -553,6 +553,8 @@ struct root_domain { }; extern struct root_domain def_root_domain; +extern void sched_get_rd(struct root_domain *rd); +extern void sched_put_rd(struct root_domain *rd); #ifdef HAVE_RT_PUSH_IPI extern void rto_push_irq_work_func(struct irq_work *work); Patches currently in stable-queue which might be from rostedt(a)goodmis.org are queue-4.4/sched-rt-use-container_of-to-get-root-domain-in-rto_push_irq_work_func.patch queue-4.4/sched-rt-up-the-root-domain-ref-count-when-passing-it-around-via-ipis.patch

6 years, 11 months

1
0
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror February 2018