- Linux-stable-mirror - lists.linaro.org

[patch 112/118] seq_file: document how per-entry resources are managed.

by Andrew Morton

From: NeilBrown <neilb(a)suse.de> Subject: seq_file: document how per-entry resources are managed. Patch series "Fix some seq_file users that were recently broken". A recent change to seq_file broke some users which were using seq_file in a non-"standard" way ... though the "standard" isn't documented, so they can be excused. The result is a possible leak - of memory in one case, of references to a 'transport' in the other. These three patches: 1/ document and explain the problem 2/ fix the problem user in x86 3/ fix the problem user in net/sctp This patch (of 3): Users of seq_file will sometimes find it convenient to take a resource, such as a lock or memory allocation, in the ->start or ->next operations. These are per-entry resources, distinct from per-session resources which are taken in ->start and released in ->stop. The preferred management of these is release the resource on the subsequent call to ->next or ->stop. However prior to Commit 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface") it happened that ->show would always be called after ->start or ->next, and a few users chose to release the resource in ->show. This is no longer reliable. Since the mentioned commit, ->next will always come after a successful ->show (to ensure m->index is updated correctly), so the original ordering cannot be maintained. This patch updates the documentation to clearly state the required behaviour. Other patches will fix the few problematic users. [akpm(a)linux-foundation.org: fix typo, per Willy] Link: https://lkml.kernel.org/r/161248518659.21478.2484341937387294998.stgit@nobl… Link: https://lkml.kernel.org/r/161248539020.21478.3147971477400875336.stgit@nobl… Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface") Signed-off-by: NeilBrown <neilb(a)suse.de> Cc: Xin Long <lucien.xin(a)gmail.com> Cc: Alexander Viro <viro(a)zeniv.linux.org.uk> Cc: Jonathan Corbet <corbet(a)lwn.net> Cc: Ingo Molnar <mingo(a)redhat.com> Cc: Dave Hansen <dave.hansen(a)linux.intel.com> Cc: Andy Lutomirski <luto(a)kernel.org> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Vlad Yasevich <vyasevich(a)gmail.com> Cc: Neil Horman <nhorman(a)tuxdriver.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner(a)gmail.com> Cc: "David S. Miller" <davem(a)davemloft.net> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- Documentation/filesystems/seq_file.rst | 6 ++++++ 1 file changed, 6 insertions(+) --- a/Documentation/filesystems/seq_file.rst~seq_file-document-how-per-entry-resources-are-managed +++ a/Documentation/filesystems/seq_file.rst @@ -217,6 +217,12 @@ between the calls to start() and stop(), is a reasonable thing to do. The seq_file code will also avoid taking any other locks while the iterator is active. +The iterater value returned by start() or next() is guaranteed to be +passed to a subsequent next() or stop() call. This allows resources +such as locks that were taken to be reliably released. There is *no* +guarantee that the iterator will be passed to show(), though in practice +it often will be. + Formatted output ================ _

4 years, 5 months

1
0
0 0

[patch 050/118] zsmalloc: account the number of compacted pages correctly

by Andrew Morton

From: Rokudo Yan <wu-yan(a)tcl.com> Subject: zsmalloc: account the number of compacted pages correctly There exists multiple path may do zram compaction concurrently. 1. auto-compaction triggered during memory reclaim 2. userspace utils write zram<id>/compaction node So, multiple threads may call zs_shrinker_scan/zs_compact concurrently. But pages_compacted is a per zsmalloc pool variable and modification of the variable is not serialized(through under class->lock). There are two issues here: 1. the pages_compacted may not equal to total number of pages freed(due to concurrently add). 2. zs_shrinker_scan may not return the correct number of pages freed(issued by current shrinker). The fix is simple: 1. account the number of pages freed in zs_compact locally. 2. use actomic variable pages_compacted to accumulate total number. Link: https://lkml.kernel.org/r/20210202122235.26885-1-wu-yan@tcl.com Fixes: 860c707dca155a56 ("zsmalloc: account the number of compacted pages") Signed-off-by: Rokudo Yan <wu-yan(a)tcl.com> Cc: Minchan Kim <minchan(a)kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky(a)gmail.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- drivers/block/zram/zram_drv.c | 2 +- include/linux/zsmalloc.h | 2 +- mm/zsmalloc.c | 17 +++++++++++------ 3 files changed, 13 insertions(+), 8 deletions(-) --- a/drivers/block/zram/zram_drv.c~zsmalloc-account-the-number-of-compacted-pages-correctly +++ a/drivers/block/zram/zram_drv.c @@ -1081,7 +1081,7 @@ static ssize_t mm_stat_show(struct devic zram->limit_pages << PAGE_SHIFT, max_used << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.same_pages), - pool_stats.pages_compacted, + atomic_long_read(&pool_stats.pages_compacted), (u64)atomic64_read(&zram->stats.huge_pages), (u64)atomic64_read(&zram->stats.huge_pages_since)); up_read(&zram->init_lock); --- a/include/linux/zsmalloc.h~zsmalloc-account-the-number-of-compacted-pages-correctly +++ a/include/linux/zsmalloc.h @@ -35,7 +35,7 @@ enum zs_mapmode { struct zs_pool_stats { /* How many pages were migrated (freed) */ - unsigned long pages_compacted; + atomic_long_t pages_compacted; }; struct zs_pool; --- a/mm/zsmalloc.c~zsmalloc-account-the-number-of-compacted-pages-correctly +++ a/mm/zsmalloc.c @@ -2212,11 +2212,13 @@ static unsigned long zs_can_compact(stru return obj_wasted * class->pages_per_zspage; } -static void __zs_compact(struct zs_pool *pool, struct size_class *class) +static unsigned long __zs_compact(struct zs_pool *pool, + struct size_class *class) { struct zs_compact_control cc; struct zspage *src_zspage; struct zspage *dst_zspage = NULL; + unsigned long pages_freed = 0; spin_lock(&class->lock); while ((src_zspage = isolate_zspage(class, true))) { @@ -2246,7 +2248,7 @@ static void __zs_compact(struct zs_pool putback_zspage(class, dst_zspage); if (putback_zspage(class, src_zspage) == ZS_EMPTY) { free_zspage(pool, class, src_zspage); - pool->stats.pages_compacted += class->pages_per_zspage; + pages_freed += class->pages_per_zspage; } spin_unlock(&class->lock); cond_resched(); @@ -2257,12 +2259,15 @@ static void __zs_compact(struct zs_pool putback_zspage(class, src_zspage); spin_unlock(&class->lock); + + return pages_freed; } unsigned long zs_compact(struct zs_pool *pool) { int i; struct size_class *class; + unsigned long pages_freed = 0; for (i = ZS_SIZE_CLASSES - 1; i >= 0; i--) { class = pool->size_class[i]; @@ -2270,10 +2275,11 @@ unsigned long zs_compact(struct zs_pool continue; if (class->index != i) continue; - __zs_compact(pool, class); + pages_freed += __zs_compact(pool, class); } + atomic_long_add(pages_freed, &pool->stats.pages_compacted); - return pool->stats.pages_compacted; + return pages_freed; } EXPORT_SYMBOL_GPL(zs_compact); @@ -2290,13 +2296,12 @@ static unsigned long zs_shrinker_scan(st struct zs_pool *pool = container_of(shrinker, struct zs_pool, shrinker); - pages_freed = pool->stats.pages_compacted; /* * Compact classes and calculate compaction delta. * Can run concurrently with a manually triggered * (by user) compaction. */ - pages_freed = zs_compact(pool) - pages_freed; + pages_freed = zs_compact(pool); return pages_freed ? pages_freed : SHRINK_STOP; } _

4 years, 5 months

1
0
0 0

✅ PASS: Test report for kernel 5.11.2-rc1 (stable)

by CKI Project

Hello, We ran automated tests on a recent commit from this kernel tree: Kernel repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git Commit: 68eabe17bf08 - Linux 5.11.2-rc1 The results of these automated tests are provided below. Overall result: PASSED Merge: OK Compile: OK Tests: OK All kernel binaries, config files, and logs are available for download here: https://arr-cki-prod-datawarehouse-public.s3.amazonaws.com/index.html?prefi… Please reply to this email if you have any questions about the tests that we ran or if you have any suggestions on how to make future tests more effective. ,-. ,-. ( C ) ( K ) Continuous `-',-.`-' Kernel ( I ) Integration `-' ______________________________________________________________________________ Compile testing --------------- We compiled the kernel for 4 architectures: aarch64: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg ppc64le: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg s390x: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg x86_64: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg Hardware testing ---------------- We booted each kernel and ran the following tests: aarch64: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ✅ Boot test ✅ ACPI table test ✅ ACPI enabled test ✅ LTP ✅ Loopdev Sanity ✅ Memory: fork_mem ✅ Memory function: memfd_create ✅ AMTU (Abstract Machine Test Utility) ✅ Networking bridge: sanity ✅ Networking socket: fuzz ✅ Networking: igmp conformance test ✅ Networking route: pmtu ✅ Networking route_func - local ⚡⚡⚡ Networking route_func - forward ⚡⚡⚡ Networking TCP: keepalive test ⚡⚡⚡ Networking UDP: socket ⚡⚡⚡ Networking tunnel: geneve basic test ⚡⚡⚡ Networking tunnel: gre basic ⚡⚡⚡ L2TP basic test ⚡⚡⚡ Networking tunnel: vxlan basic ⚡⚡⚡ Networking ipsec: basic netns - transport ⚡⚡⚡ Networking ipsec: basic netns - tunnel ⚡⚡⚡ Libkcapi AF_ALG test ⚡⚡⚡ pciutils: update pci ids test ⚡⚡⚡ ALSA PCM loopback test ⚡⚡⚡ ALSA Control (mixer) Userspace Element test ⚡⚡⚡ storage: SCSI VPD ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ Firmware test suite 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test ppc64le: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ✅ Boot test ✅ LTP ✅ Loopdev Sanity ✅ Memory: fork_mem ✅ Memory function: memfd_create ✅ AMTU (Abstract Machine Test Utility) ✅ Networking bridge: sanity ✅ Networking socket: fuzz ✅ Networking route: pmtu ✅ Networking route_func - local ✅ Networking route_func - forward ✅ Networking TCP: keepalive test ✅ Networking UDP: socket ✅ Networking tunnel: geneve basic test ✅ Networking tunnel: gre basic ✅ L2TP basic test ✅ Networking tunnel: vxlan basic ✅ Networking ipsec: basic netns - tunnel ✅ Libkcapi AF_ALG test ✅ pciutils: update pci ids test ⚡⚡⚡ ALSA PCM loopback test ⚡⚡⚡ ALSA Control (mixer) Userspace Element test ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test s390x: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ✅ Boot test ⚡⚡⚡ LTP ⚡⚡⚡ Loopdev Sanity ⚡⚡⚡ Memory: fork_mem ⚡⚡⚡ Memory function: memfd_create ⚡⚡⚡ AMTU (Abstract Machine Test Utility) ⚡⚡⚡ Networking bridge: sanity ⚡⚡⚡ Networking route: pmtu ⚡⚡⚡ Networking route_func - local ⚡⚡⚡ Networking route_func - forward ⚡⚡⚡ Networking TCP: keepalive test ⚡⚡⚡ Networking UDP: socket ⚡⚡⚡ Networking tunnel: geneve basic test ⚡⚡⚡ Networking tunnel: gre basic ⚡⚡⚡ L2TP basic test ⚡⚡⚡ Networking tunnel: vxlan basic ⚡⚡⚡ Networking ipsec: basic netns - transport ⚡⚡⚡ Networking ipsec: basic netns - tunnel ⚡⚡⚡ Libkcapi AF_ALG test ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test x86_64: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ✅ Boot test ✅ ACPI table test ⚡⚡⚡ LTP ⚡⚡⚡ Loopdev Sanity ⚡⚡⚡ Memory: fork_mem ⚡⚡⚡ Memory function: memfd_create ⚡⚡⚡ AMTU (Abstract Machine Test Utility) ⚡⚡⚡ Networking bridge: sanity ⚡⚡⚡ Networking socket: fuzz ⚡⚡⚡ Networking: igmp conformance test ⚡⚡⚡ Networking route: pmtu ⚡⚡⚡ Networking route_func - local ⚡⚡⚡ Networking route_func - forward ⚡⚡⚡ Networking TCP: keepalive test ⚡⚡⚡ Networking UDP: socket ⚡⚡⚡ Networking tunnel: geneve basic test ⚡⚡⚡ Networking tunnel: gre basic ⚡⚡⚡ L2TP basic test ⚡⚡⚡ Networking tunnel: vxlan basic ⚡⚡⚡ Networking ipsec: basic netns - transport ⚡⚡⚡ Networking ipsec: basic netns - tunnel ⚡⚡⚡ Libkcapi AF_ALG test ⚡⚡⚡ pciutils: sanity smoke test ⚡⚡⚡ pciutils: update pci ids test ⚡⚡⚡ ALSA PCM loopback test ⚡⚡⚡ ALSA Control (mixer) Userspace Element test ⚡⚡⚡ storage: SCSI VPD ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ Firmware test suite 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test Test sources: https://gitlab.com/cki-project/kernel-tests 💚 Pull requests are welcome for new tests or improvements to existing tests! Aborted tests ------------- Tests that didn't complete running successfully are marked with ⚡⚡⚡. If this was caused by an infrastructure issue, we try to mark that explicitly in the report. Waived tests ------------ If the test run included waived tests, they are marked with 🚧. Such tests are executed but their results are not taken into account. Tests are waived when their results are not reliable enough, e.g. when they're just introduced or are being fixed. Testing timeout --------------- We aim to provide a report within reasonable timeframe. Tests that haven't finished running yet are marked with ⏱.

4 years, 5 months

1
0
0 0

[PATCH v3] drm: Use USB controller's DMA mask when importing dmabufs

by Thomas Zimmermann

USB devices cannot perform DMA and hence have no dma_mask set in their device structure. Importing dmabuf into a USB-based driver fails, which break joining and mirroring of display in X11. For USB devices, pick the associated USB controller as attachment device, so that it can perform DMA. If the DMa controller does not support DMA transfers, we're aout of luck and cannot import. Drivers should use DRM_GEM_SHMEM_DROVER_OPS_USB to initialize their instance of struct drm_driver. Tested by joining/mirroring displays of udl and radeon un der Gnome/X11. v3: * drop gem_create_object * use DMA mask of USB controller, if any (Daniel, Christian, Noralf) v2: * move fix to importer side (Christian, Daniel) * update SHMEM and CMA helpers for new PRIME callbacks Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de> Fixes: 6eb0233ec2d0 ("usb: don't inherity DMA properties for USB devices") Cc: Christoph Hellwig <hch(a)lst.de> Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Cc: Johan Hovold <johan(a)kernel.org> Cc: Alan Stern <stern(a)rowland.harvard.edu> Cc: Andy Shevchenko <andriy.shevchenko(a)linux.intel.com> Cc: Sebastian Andrzej Siewior <bigeasy(a)linutronix.de> Cc: Mathias Nyman <mathias.nyman(a)linux.intel.com> Cc: Oliver Neukum <oneukum(a)suse.com> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: <stable(a)vger.kernel.org> # v5.10+ --- drivers/gpu/drm/drm_prime.c | 36 ++++++++++++++++++++++++++++++ drivers/gpu/drm/tiny/gm12u320.c | 2 +- drivers/gpu/drm/udl/udl_drv.c | 2 +- include/drm/drm_gem_shmem_helper.h | 13 +++++++++++ include/drm/drm_prime.h | 5 +++++ 5 files changed, 56 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 2a54f86856af..9015850f2160 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -29,6 +29,7 @@ #include <linux/export.h> #include <linux/dma-buf.h> #include <linux/rbtree.h> +#include <linux/usb.h> #include <drm/drm.h> #include <drm/drm_drv.h> @@ -1055,3 +1056,38 @@ void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg) dma_buf_put(dma_buf); } EXPORT_SYMBOL(drm_prime_gem_destroy); + +/** + * drm_gem_prime_import_usb - helper library implementation of the import callback for USB devices + * @dev: drm_device to import into + * @dma_buf: dma-buf object to import + * + * This is an implementation of drm_gem_prime_import() for USB-based devices. + * USB devices cannot perform DMA directly. This function selects the USB host + * controller as DMA device instead. Drivers can use this as their + * &drm_driver.gem_prime_import implementation. + * + * See also drm_gem_prime_import(). + */ +#ifdef CONFIG_USB +struct drm_gem_object *drm_gem_prime_import_usb(struct drm_device *dev, + struct dma_buf *dma_buf) +{ + struct usb_device *udev; + struct device *usbhost; + + if (dev->dev->bus != &usb_bus_type) + return ERR_PTR(-ENODEV); + + udev = interface_to_usbdev(to_usb_interface(dev->dev)); + if (!udev->bus) + return ERR_PTR(-ENODEV); + + usbhost = udev->bus->controller; + if (!usbhost || !usbhost->dma_mask) + return ERR_PTR(-ENODEV); + + return drm_gem_prime_import_dev(dev, dma_buf, usbhost); +} +EXPORT_SYMBOL(drm_gem_prime_import_usb); +#endif diff --git a/drivers/gpu/drm/tiny/gm12u320.c b/drivers/gpu/drm/tiny/gm12u320.c index 0b4f4f2af1ef..99e7bd36a220 100644 --- a/drivers/gpu/drm/tiny/gm12u320.c +++ b/drivers/gpu/drm/tiny/gm12u320.c @@ -611,7 +611,7 @@ static const struct drm_driver gm12u320_drm_driver = { .minor = DRIVER_MINOR, .fops = &gm12u320_fops, - DRM_GEM_SHMEM_DRIVER_OPS, + DRM_GEM_SHMEM_DRIVER_OPS_USB, }; static const struct drm_mode_config_funcs gm12u320_mode_config_funcs = { diff --git a/drivers/gpu/drm/udl/udl_drv.c b/drivers/gpu/drm/udl/udl_drv.c index 9269092697d8..2db483b2b199 100644 --- a/drivers/gpu/drm/udl/udl_drv.c +++ b/drivers/gpu/drm/udl/udl_drv.c @@ -39,7 +39,7 @@ static const struct drm_driver driver = { /* GEM hooks */ .fops = &udl_driver_fops, - DRM_GEM_SHMEM_DRIVER_OPS, + DRM_GEM_SHMEM_DRIVER_OPS_USB, .name = DRIVER_NAME, .desc = DRIVER_DESC, diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index 434328d8a0d9..09d12f632cad 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -162,4 +162,17 @@ struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_object *obj); .gem_prime_mmap = drm_gem_prime_mmap, \ .dumb_create = drm_gem_shmem_dumb_create +#ifdef CONFIG_USB +/** + * DRM_GEM_SHMEM_DRIVER_OPS_USB - Default shmem GEM operations for USB devices + * + * This macro provides a shortcut for setting the shmem GEM operations in + * the &drm_driver structure. Drivers for USB-based devices should use this + * macro instead of &DRM_GEM_SHMEM_DRIVER_OPS. + */ +#define DRM_GEM_SHMEM_DRIVER_OPS_USB \ + DRM_GEM_SHMEM_DRIVER_OPS, \ + .gem_prime_import = drm_gem_prime_import_usb +#endif + #endif /* __DRM_GEM_SHMEM_HELPER_H__ */ diff --git a/include/drm/drm_prime.h b/include/drm/drm_prime.h index 54f2c58305d2..b42e07edd9e6 100644 --- a/include/drm/drm_prime.h +++ b/include/drm/drm_prime.h @@ -110,4 +110,9 @@ int drm_prime_sg_to_page_array(struct sg_table *sgt, struct page **pages, int drm_prime_sg_to_dma_addr_array(struct sg_table *sgt, dma_addr_t *addrs, int max_pages); +#ifdef CONFIG_USB +struct drm_gem_object *drm_gem_prime_import_usb(struct drm_device *dev, + struct dma_buf *dma_buf); +#endif + #endif /* __DRM_PRIME_H__ */ -- 2.30.1

4 years, 5 months

8
28
0 0

[RFC 1/1] s390/vfio-ap: fix circular lockdep when setting/clearing crypto masks

by Tony Krowiak

This patch fixes a circular locking dependency in the CI introduced by commit f21916ec4826 ("s390/vfio-ap: clean up vfio_ap resources when KVM pointer invalidated"). The lockdep only occurs when starting a Secure Execution guest. Crypto virtualization (vfio_ap) is not yet supported for SE guests; however, in order to avoid CI errors, this fix is being provided. The circular lockdep was introduced when the masks in the guest's APCB were taken under the matrix_dev->lock. While the lock is definitely needed to protect the setting/unsetting of the KVM pointer, it is not necessarily critical for setting the masks, so this will not be done under protection of the matrix_dev->lock. Fixes: f21916ec4826 ("s390/vfio-ap: clean up vfio_ap resources when KVM pointer invalidated") Cc: stable(a)vger.kernel.org Signed-off-by: Tony Krowiak <akrowiak(a)linux.ibm.com> Acked-by: Cornelia Huck <cohuck(a)redhat.com> --- drivers/s390/crypto/vfio_ap_ops.c | 169 ++++++++++++++++++-------- drivers/s390/crypto/vfio_ap_private.h | 1 + 2 files changed, 122 insertions(+), 48 deletions(-) diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index 41fc2e4135fe..82b204f573b7 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -294,6 +294,21 @@ static int handle_pqap(struct kvm_vcpu *vcpu) matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook, struct ap_matrix_mdev, pqap_hook); + /* + * If the KVM pointer is in the process of being set, wait until the + * process has completed. Unlock the matrix_dev->lock while waiting to + * allow the value of the KVM pointer to be set. + */ + while (matrix_mdev->kvm_busy) { + mutex_unlock(&matrix_dev->lock); + msleep(100); + mutex_lock(&matrix_dev->lock); + } + + /* If the there is no guest using the mdev, there is nothing to do */ + if (!matrix_mdev->kvm) + goto out_unlock; + q = vfio_ap_get_queue(matrix_mdev, apqn); if (!q) goto out_unlock; @@ -350,8 +365,11 @@ static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) static int vfio_ap_mdev_remove(struct mdev_device *mdev) { struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); - - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * removal of the mdev + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; mutex_lock(&matrix_dev->lock); @@ -606,8 +624,11 @@ static ssize_t assign_adapter_store(struct device *dev, struct mdev_device *mdev = mdev_from_dev(dev); struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); - /* If the guest is running, disallow assignment of adapter */ - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * un-assignment of adapter + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; ret = kstrtoul(buf, 0, &apid); @@ -672,8 +693,11 @@ static ssize_t unassign_adapter_store(struct device *dev, struct mdev_device *mdev = mdev_from_dev(dev); struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); - /* If the guest is running, disallow un-assignment of adapter */ - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * un-assignment of adapter + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; ret = kstrtoul(buf, 0, &apid); @@ -753,8 +777,11 @@ static ssize_t assign_domain_store(struct device *dev, struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); unsigned long max_apqi = matrix_mdev->matrix.aqm_max; - /* If the guest is running, disallow assignment of domain */ - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * un-assignment of domain + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; ret = kstrtoul(buf, 0, &apqi); @@ -814,8 +841,11 @@ static ssize_t unassign_domain_store(struct device *dev, struct mdev_device *mdev = mdev_from_dev(dev); struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); - /* If the guest is running, disallow un-assignment of domain */ - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * un-assignment of domain + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; ret = kstrtoul(buf, 0, &apqi); @@ -858,8 +888,11 @@ static ssize_t assign_control_domain_store(struct device *dev, struct mdev_device *mdev = mdev_from_dev(dev); struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); - /* If the guest is running, disallow assignment of control domain */ - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * un-assignment of control domain + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; ret = kstrtoul(buf, 0, &id); @@ -908,8 +941,11 @@ static ssize_t unassign_control_domain_store(struct device *dev, struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); unsigned long max_domid = matrix_mdev->matrix.adm_max; - /* If the guest is running, disallow un-assignment of control domain */ - if (matrix_mdev->kvm) + /* + * If the KVM pointer is in flux or the guest is running, disallow + * un-assignment of control domain + */ + if (matrix_mdev->kvm_busy || matrix_mdev->kvm) return -EBUSY; ret = kstrtoul(buf, 0, &domid); @@ -1027,8 +1063,15 @@ static const struct attribute_group *vfio_ap_mdev_attr_groups[] = { * @matrix_mdev: a mediated matrix device * @kvm: reference to KVM instance * - * Verifies no other mediated matrix device has @kvm and sets a reference to - * it in @matrix_mdev->kvm. + * Sets all data for @matrix_mdev that are needed to manage AP resources + * for the guest whose state is represented by @kvm. + * + * Note: The matrix_dev->lock must be taken prior to calling + * this function; however, the lock will be temporarily released while the + * guest's AP configuration is set to avoid a potential lockdep splat. + * The kvm->lock is taken to set the guest's AP configuration which, under + * certain circumstances, will result in a circular lock dependency if this is + * done under the @matrix_mdev->lock. * * Return 0 if no other mediated matrix device has a reference to @kvm; * otherwise, returns an -EPERM. @@ -1043,9 +1086,18 @@ static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev, return -EPERM; } - matrix_mdev->kvm = kvm; - kvm_get_kvm(kvm); - kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook; + if (kvm->arch.crypto.crycbd) { + matrix_mdev->kvm_busy = true; + kvm_get_kvm(kvm); + mutex_unlock(&matrix_dev->lock); + kvm_arch_crypto_set_masks(kvm, + matrix_mdev->matrix.apm, + matrix_mdev->matrix.aqm, + matrix_mdev->matrix.adm); + mutex_lock(&matrix_dev->lock); + matrix_mdev->kvm = kvm; + matrix_mdev->kvm_busy = false; + } return 0; } @@ -1079,51 +1131,54 @@ static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb, return NOTIFY_DONE; } +/** + * vfio_ap_mdev_unset_kvm + * + * @matrix_mdev: a matrix mediated device + * + * Performs clean-up of resources no longer needed by @matrix_mdev. + * + * Note: The matrix_dev->lock must be taken prior to calling + * this function; however, the lock will be temporarily released while the + * guest's AP configuration is cleared to avoid a potential lockdep splat. + * The kvm->lock is taken to clear the guest's AP configuration which, under + * certain circumstances, will result in a circular lock dependency if this is + * done under the @matrix_mdev->lock. + * + */ static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev) { - kvm_arch_crypto_clear_masks(matrix_mdev->kvm); - matrix_mdev->kvm->arch.crypto.pqap_hook = NULL; - vfio_ap_mdev_reset_queues(matrix_mdev->mdev); - kvm_put_kvm(matrix_mdev->kvm); - matrix_mdev->kvm = NULL; + if (matrix_mdev->kvm) { + matrix_mdev->kvm_busy = true; + mutex_unlock(&matrix_dev->lock); + kvm_arch_crypto_clear_masks(matrix_mdev->kvm); + mutex_lock(&matrix_dev->lock); + vfio_ap_mdev_reset_queues(matrix_mdev->mdev); + kvm_put_kvm(matrix_mdev->kvm); + matrix_mdev->kvm = NULL; + matrix_mdev->kvm_busy = false; + } } static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, unsigned long action, void *data) { - int ret, notify_rc = NOTIFY_OK; + int notify_rc = NOTIFY_OK; struct ap_matrix_mdev *matrix_mdev; if (action != VFIO_GROUP_NOTIFY_SET_KVM) return NOTIFY_OK; - matrix_mdev = container_of(nb, struct ap_matrix_mdev, group_notifier); mutex_lock(&matrix_dev->lock); + matrix_mdev = container_of(nb, struct ap_matrix_mdev, group_notifier); - if (!data) { - if (matrix_mdev->kvm) - vfio_ap_mdev_unset_kvm(matrix_mdev); - goto notify_done; - } - - ret = vfio_ap_mdev_set_kvm(matrix_mdev, data); - if (ret) { - notify_rc = NOTIFY_DONE; - goto notify_done; - } - - /* If there is no CRYCB pointer, then we can't copy the masks */ - if (!matrix_mdev->kvm->arch.crypto.crycbd) { + if (!data) + vfio_ap_mdev_unset_kvm(matrix_mdev); + else if (vfio_ap_mdev_set_kvm(matrix_mdev, data)) notify_rc = NOTIFY_DONE; - goto notify_done; - } - - kvm_arch_crypto_set_masks(matrix_mdev->kvm, matrix_mdev->matrix.apm, - matrix_mdev->matrix.aqm, - matrix_mdev->matrix.adm); -notify_done: mutex_unlock(&matrix_dev->lock); + return notify_rc; } @@ -1258,8 +1313,20 @@ static void vfio_ap_mdev_release(struct mdev_device *mdev) struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); mutex_lock(&matrix_dev->lock); + /* + * If the KVM pointer is in the process of being set, wait until the + * process has completed. Unlock the matrix_dev->lock while waiting to + * allow the value of the KVM pointer to be set. + */ + while (matrix_mdev->kvm_busy) { + mutex_unlock(&matrix_dev->lock); + msleep(100); + mutex_lock(&matrix_dev->lock); + } + if (matrix_mdev->kvm) vfio_ap_mdev_unset_kvm(matrix_mdev); + mutex_unlock(&matrix_dev->lock); vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, @@ -1293,6 +1360,7 @@ static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev, unsigned int cmd, unsigned long arg) { int ret; + struct ap_matrix_mdev *matrix_mdev; mutex_lock(&matrix_dev->lock); switch (cmd) { @@ -1300,7 +1368,12 @@ static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev, ret = vfio_ap_mdev_get_device_info(arg); break; case VFIO_DEVICE_RESET: - ret = vfio_ap_mdev_reset_queues(mdev); + matrix_mdev = mdev_get_drvdata(mdev); + + if (matrix_mdev->kvm_busy) + ret = -EBUSY; + else + ret = vfio_ap_mdev_reset_queues(mdev); break; default: ret = -EOPNOTSUPP; diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h index 28e9d9989768..d1c8d25a899e 100644 --- a/drivers/s390/crypto/vfio_ap_private.h +++ b/drivers/s390/crypto/vfio_ap_private.h @@ -83,6 +83,7 @@ struct ap_matrix_mdev { struct ap_matrix matrix; struct notifier_block group_notifier; struct notifier_block iommu_notifier; + bool kvm_busy; struct kvm *kvm; struct kvm_s390_module_hook pqap_hook; struct mdev_device *mdev; -- 2.21.3

4 years, 5 months

1
0
0 0

[GIT PULL] virtio: features, fixes

by Michael S. Tsirkin

There are a couple new drivers and support for the new management interface for mlx under review now. I figured I'll send them separately if review is done in time, lots of people are waiting for the vdpa tool patches to I want to make sure they make this release. The following changes since commit f40ddce88593482919761f74910f42f4b84c004b: Linux 5.11 (2021-02-14 14:32:24 -0800) are available in the Git repository at: https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git tags/for_linus for you to fetch changes up to 16c10bede8b3d8594279752bf53153491f3f944f: virtio-input: add multi-touch support (2021-02-23 07:52:59 -0500) ---------------------------------------------------------------- virtio: features, fixes new vdpa features to allow creation and deletion of new devices virtio-blk support per-device queue depth fixes, cleanups all over the place Signed-off-by: Michael S. Tsirkin <mst(a)redhat.com> ---------------------------------------------------------------- Colin Xu (1): virtio_input: Prevent EV_MSC/MSC_TIMESTAMP loop storm for MT. Dongli Zhang (1): vhost scsi: alloc vhost_scsi with kvzalloc() to avoid delay Gustavo A. R. Silva (1): virtio_net: Fix fall-through warnings for Clang Jason Wang (17): virtio-pci: do not access iomem via struct virtio_pci_device directly virtio-pci: split out modern device virtio-pci-modern: factor out modern device initialization logic virtio-pci-modern: introduce vp_modern_remove() virtio-pci-modern: introduce helper to set config vector virtio-pci-modern: introduce helpers for setting and getting status virtio-pci-modern: introduce helpers for setting and getting features virtio-pci-modern: introduce vp_modern_generation() virtio-pci-modern: introduce vp_modern_set_queue_vector() virtio-pci-modern: introduce vp_modern_queue_address() virtio-pci-modern: introduce helper to set/get queue_enable virtio-pci-modern: introduce helper for setting/geting queue size virtio-pci-modern: introduce helper for getting queue nums virtio-pci-modern: introduce helper to get notification offset virito-pci-modern: rename map_capability() to vp_modern_map_capability() virtio-pci: introduce modern device module virtio_vdpa: don't warn when fail to disable vq Jiapeng Zhong (1): virtio-mem: Assign boolean values to a bool variable Joseph Qi (1): virtio-blk: support per-device queue depth Mathias Crombez (1): virtio-input: add multi-touch support Parav Pandit (6): vdpa_sim_net: Make mac address array static vdpa: Extend routine to accept vdpa device name vdpa: Define vdpa mgmt device, ops and a netlink interface vdpa: Enable a user to add and delete a vdpa device vdpa: Enable user to query vdpa device info vdpa_sim_net: Add support for user supported devices Stefano Garzarella (1): vdpa/mlx5: fix param validation in mlx5_vdpa_get_config() Xianting Tian (1): virtio_mmio: fix one typo drivers/block/virtio_blk.c | 11 +- drivers/net/virtio_net.c | 1 + drivers/vdpa/Kconfig | 1 + drivers/vdpa/ifcvf/ifcvf_main.c | 2 +- drivers/vdpa/mlx5/net/mlx5_vnet.c | 4 +- drivers/vdpa/vdpa.c | 503 ++++++++++++++++++++++++++- drivers/vdpa/vdpa_sim/vdpa_sim.c | 3 +- drivers/vdpa/vdpa_sim/vdpa_sim.h | 2 + drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 100 ++++-- drivers/vhost/scsi.c | 9 +- drivers/virtio/Kconfig | 9 + drivers/virtio/Makefile | 1 + drivers/virtio/virtio_input.c | 26 +- drivers/virtio/virtio_mem.c | 2 +- drivers/virtio/virtio_mmio.c | 2 +- drivers/virtio/virtio_pci_common.h | 22 +- drivers/virtio/virtio_pci_modern.c | 504 ++++----------------------- drivers/virtio/virtio_pci_modern_dev.c | 599 +++++++++++++++++++++++++++++++++ drivers/virtio/virtio_vdpa.c | 3 +- include/linux/vdpa.h | 44 ++- include/linux/virtio_pci_modern.h | 111 ++++++ include/uapi/linux/vdpa.h | 40 +++ 22 files changed, 1492 insertions(+), 507 deletions(-) create mode 100644 drivers/virtio/virtio_pci_modern_dev.c create mode 100644 include/linux/virtio_pci_modern.h create mode 100644 include/uapi/linux/vdpa.h

4 years, 5 months

2
1
0 0

FAILED: patch "[PATCH] mm: hugetlb: fix a race between freeing and dissolving the" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 7ffddd499ba6122b1a07828f023d1d67629aa017 Mon Sep 17 00:00:00 2001 From: Muchun Song <songmuchun(a)bytedance.com> Date: Thu, 4 Feb 2021 18:32:06 -0800 Subject: [PATCH] mm: hugetlb: fix a race between freeing and dissolving the page There is a race condition between __free_huge_page() and dissolve_free_huge_page(). CPU0: CPU1: // page_count(page) == 1 put_page(page) __free_huge_page(page) dissolve_free_huge_page(page) spin_lock(&hugetlb_lock) // PageHuge(page) && !page_count(page) update_and_free_page(page) // page is freed to the buddy spin_unlock(&hugetlb_lock) spin_lock(&hugetlb_lock) clear_page_huge_active(page) enqueue_huge_page(page) // It is wrong, the page is already freed spin_unlock(&hugetlb_lock) The race window is between put_page() and dissolve_free_huge_page(). We should make sure that the page is already on the free list when it is dissolved. As a result __free_huge_page would corrupt page(s) already in the buddy allocator. Link: https://lkml.kernel.org/r/20210115124942.46403-4-songmuchun@bytedance.com Fixes: c8721bbbdd36 ("mm: memory-hotplug: enable memory hotplug to handle hugepage") Signed-off-by: Muchun Song <songmuchun(a)bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz(a)oracle.com> Reviewed-by: Oscar Salvador <osalvador(a)suse.de> Acked-by: Michal Hocko <mhocko(a)suse.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: Yang Shi <shy828301(a)gmail.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 6f0e242d38ca..c6ee3c28a04e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -79,6 +79,21 @@ DEFINE_SPINLOCK(hugetlb_lock); static int num_fault_mutexes; struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; +static inline bool PageHugeFreed(struct page *head) +{ + return page_private(head + 4) == -1UL; +} + +static inline void SetPageHugeFreed(struct page *head) +{ + set_page_private(head + 4, -1UL); +} + +static inline void ClearPageHugeFreed(struct page *head) +{ + set_page_private(head + 4, 0); +} + /* Forward declaration */ static int hugetlb_acct_memory(struct hstate *h, long delta); @@ -1028,6 +1043,7 @@ static void enqueue_huge_page(struct hstate *h, struct page *page) list_move(&page->lru, &h->hugepage_freelists[nid]); h->free_huge_pages++; h->free_huge_pages_node[nid]++; + SetPageHugeFreed(page); } static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) @@ -1044,6 +1060,7 @@ static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) list_move(&page->lru, &h->hugepage_activelist); set_page_refcounted(page); + ClearPageHugeFreed(page); h->free_huge_pages--; h->free_huge_pages_node[nid]--; return page; @@ -1505,6 +1522,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) spin_lock(&hugetlb_lock); h->nr_huge_pages++; h->nr_huge_pages_node[nid]++; + ClearPageHugeFreed(page); spin_unlock(&hugetlb_lock); } @@ -1755,6 +1773,7 @@ int dissolve_free_huge_page(struct page *page) { int rc = -EBUSY; +retry: /* Not to disrupt normal path by vainly holding hugetlb_lock */ if (!PageHuge(page)) return 0; @@ -1771,6 +1790,26 @@ int dissolve_free_huge_page(struct page *page) int nid = page_to_nid(head); if (h->free_huge_pages - h->resv_huge_pages == 0) goto out; + + /* + * We should make sure that the page is already on the free list + * when it is dissolved. + */ + if (unlikely(!PageHugeFreed(head))) { + spin_unlock(&hugetlb_lock); + cond_resched(); + + /* + * Theoretically, we should return -EBUSY when we + * encounter this race. In fact, we have a chance + * to successfully dissolve the page if we do a + * retry. Because the race window is quite small. + * If we seize this opportunity, it is an optimization + * for increasing the success rate of dissolving page. + */ + goto retry; + } + /* * Move PageHWPoison flag from head page to the raw error page, * which makes any subpages rather than the error page reusable.

4 years, 5 months

2
1
0 0

FAILED: patch "[PATCH] mm: hugetlb: fix a race between freeing and dissolving the" failed to apply to 4.14-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 7ffddd499ba6122b1a07828f023d1d67629aa017 Mon Sep 17 00:00:00 2001 From: Muchun Song <songmuchun(a)bytedance.com> Date: Thu, 4 Feb 2021 18:32:06 -0800 Subject: [PATCH] mm: hugetlb: fix a race between freeing and dissolving the page There is a race condition between __free_huge_page() and dissolve_free_huge_page(). CPU0: CPU1: // page_count(page) == 1 put_page(page) __free_huge_page(page) dissolve_free_huge_page(page) spin_lock(&hugetlb_lock) // PageHuge(page) && !page_count(page) update_and_free_page(page) // page is freed to the buddy spin_unlock(&hugetlb_lock) spin_lock(&hugetlb_lock) clear_page_huge_active(page) enqueue_huge_page(page) // It is wrong, the page is already freed spin_unlock(&hugetlb_lock) The race window is between put_page() and dissolve_free_huge_page(). We should make sure that the page is already on the free list when it is dissolved. As a result __free_huge_page would corrupt page(s) already in the buddy allocator. Link: https://lkml.kernel.org/r/20210115124942.46403-4-songmuchun@bytedance.com Fixes: c8721bbbdd36 ("mm: memory-hotplug: enable memory hotplug to handle hugepage") Signed-off-by: Muchun Song <songmuchun(a)bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz(a)oracle.com> Reviewed-by: Oscar Salvador <osalvador(a)suse.de> Acked-by: Michal Hocko <mhocko(a)suse.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: Yang Shi <shy828301(a)gmail.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 6f0e242d38ca..c6ee3c28a04e 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -79,6 +79,21 @@ DEFINE_SPINLOCK(hugetlb_lock); static int num_fault_mutexes; struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; +static inline bool PageHugeFreed(struct page *head) +{ + return page_private(head + 4) == -1UL; +} + +static inline void SetPageHugeFreed(struct page *head) +{ + set_page_private(head + 4, -1UL); +} + +static inline void ClearPageHugeFreed(struct page *head) +{ + set_page_private(head + 4, 0); +} + /* Forward declaration */ static int hugetlb_acct_memory(struct hstate *h, long delta); @@ -1028,6 +1043,7 @@ static void enqueue_huge_page(struct hstate *h, struct page *page) list_move(&page->lru, &h->hugepage_freelists[nid]); h->free_huge_pages++; h->free_huge_pages_node[nid]++; + SetPageHugeFreed(page); } static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) @@ -1044,6 +1060,7 @@ static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) list_move(&page->lru, &h->hugepage_activelist); set_page_refcounted(page); + ClearPageHugeFreed(page); h->free_huge_pages--; h->free_huge_pages_node[nid]--; return page; @@ -1505,6 +1522,7 @@ static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) spin_lock(&hugetlb_lock); h->nr_huge_pages++; h->nr_huge_pages_node[nid]++; + ClearPageHugeFreed(page); spin_unlock(&hugetlb_lock); } @@ -1755,6 +1773,7 @@ int dissolve_free_huge_page(struct page *page) { int rc = -EBUSY; +retry: /* Not to disrupt normal path by vainly holding hugetlb_lock */ if (!PageHuge(page)) return 0; @@ -1771,6 +1790,26 @@ int dissolve_free_huge_page(struct page *page) int nid = page_to_nid(head); if (h->free_huge_pages - h->resv_huge_pages == 0) goto out; + + /* + * We should make sure that the page is already on the free list + * when it is dissolved. + */ + if (unlikely(!PageHugeFreed(head))) { + spin_unlock(&hugetlb_lock); + cond_resched(); + + /* + * Theoretically, we should return -EBUSY when we + * encounter this race. In fact, we have a chance + * to successfully dissolve the page if we do a + * retry. Because the race window is quite small. + * If we seize this opportunity, it is an optimization + * for increasing the success rate of dissolving page. + */ + goto retry; + } + /* * Move PageHWPoison flag from head page to the raw error page, * which makes any subpages rather than the error page reusable.

4 years, 5 months

2
1
0 0

✅ PASS: Test report for kernel 5.11.1 (stable-queue)

by CKI Project

Hello, We ran automated tests on a recent commit from this kernel tree: Kernel repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git Commit: 9c7a62998dea - KVM: Use kvm_pfn_t for local PFN variable in hva_to_pfn_remapped() The results of these automated tests are provided below. Overall result: PASSED Merge: OK Compile: OK Tests: OK All kernel binaries, config files, and logs are available for download here: https://arr-cki-prod-datawarehouse-public.s3.amazonaws.com/index.html?prefi… Please reply to this email if you have any questions about the tests that we ran or if you have any suggestions on how to make future tests more effective. ,-. ,-. ( C ) ( K ) Continuous `-',-.`-' Kernel ( I ) Integration `-' ______________________________________________________________________________ Compile testing --------------- We compiled the kernel for 4 architectures: aarch64: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg ppc64le: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg s390x: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg x86_64: make options: make -j30 INSTALL_MOD_STRIP=1 targz-pkg Hardware testing ---------------- We booted each kernel and ran the following tests: aarch64: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ✅ Boot test ✅ ACPI table test ✅ ACPI enabled test ✅ LTP ✅ Loopdev Sanity ✅ Memory: fork_mem ✅ Memory function: memfd_create ✅ AMTU (Abstract Machine Test Utility) ✅ Networking bridge: sanity ✅ Networking socket: fuzz ⏱ Networking: igmp conformance test ⚡⚡⚡ Networking route: pmtu ⚡⚡⚡ Networking route_func - local ⚡⚡⚡ Networking route_func - forward ⚡⚡⚡ Networking TCP: keepalive test ⚡⚡⚡ Networking UDP: socket ⚡⚡⚡ Networking tunnel: geneve basic test ⚡⚡⚡ Networking tunnel: gre basic ⚡⚡⚡ L2TP basic test ⚡⚡⚡ Networking tunnel: vxlan basic ⚡⚡⚡ Networking ipsec: basic netns - transport ⚡⚡⚡ Networking ipsec: basic netns - tunnel ⚡⚡⚡ Libkcapi AF_ALG test ⚡⚡⚡ pciutils: update pci ids test ⚡⚡⚡ ALSA PCM loopback test ⚡⚡⚡ ALSA Control (mixer) Userspace Element test ⚡⚡⚡ storage: SCSI VPD ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ Firmware test suite 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test ppc64le: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ⚡⚡⚡ Boot test ⚡⚡⚡ selinux-policy: serge-testsuite ⚡⚡⚡ storage: software RAID testing 🚧 ⚡⚡⚡ xfstests - ext4 🚧 ⚡⚡⚡ xfstests - xfs 🚧 ⚡⚡⚡ xfstests - btrfs 🚧 ⚡⚡⚡ IPMI driver test 🚧 ⚡⚡⚡ IPMItool loop stress test 🚧 ⚡⚡⚡ Storage blktests 🚧 ⚡⚡⚡ Storage block - filesystem fio test 🚧 ⚡⚡⚡ Storage block - queue scheduler test 🚧 ⚡⚡⚡ Storage nvme - tcp 🚧 ⚡⚡⚡ Storage: swraid mdadm raid_module test Host 2: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ⚡⚡⚡ Boot test ⚡⚡⚡ LTP ⚡⚡⚡ Loopdev Sanity ⚡⚡⚡ Memory: fork_mem ⚡⚡⚡ Memory function: memfd_create ⚡⚡⚡ AMTU (Abstract Machine Test Utility) ⚡⚡⚡ Networking bridge: sanity ⚡⚡⚡ Networking socket: fuzz ⚡⚡⚡ Networking route: pmtu ⚡⚡⚡ Networking route_func - local ⚡⚡⚡ Networking route_func - forward ⚡⚡⚡ Networking TCP: keepalive test ⚡⚡⚡ Networking UDP: socket ⚡⚡⚡ Networking tunnel: geneve basic test ⚡⚡⚡ Networking tunnel: gre basic ⚡⚡⚡ L2TP basic test ⚡⚡⚡ Networking tunnel: vxlan basic ⚡⚡⚡ Networking ipsec: basic netns - tunnel ⚡⚡⚡ Libkcapi AF_ALG test ⚡⚡⚡ pciutils: update pci ids test ⚡⚡⚡ ALSA PCM loopback test ⚡⚡⚡ ALSA Control (mixer) Userspace Element test ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test s390x: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ✅ Boot test ⚡⚡⚡ LTP ⚡⚡⚡ Loopdev Sanity ⚡⚡⚡ Memory: fork_mem ⚡⚡⚡ Memory function: memfd_create ⚡⚡⚡ AMTU (Abstract Machine Test Utility) ⚡⚡⚡ Networking bridge: sanity ⚡⚡⚡ Networking route: pmtu ⚡⚡⚡ Networking route_func - local ⚡⚡⚡ Networking route_func - forward ⚡⚡⚡ Networking TCP: keepalive test ⚡⚡⚡ Networking UDP: socket ⚡⚡⚡ Networking tunnel: geneve basic test ⚡⚡⚡ Networking tunnel: gre basic ⚡⚡⚡ L2TP basic test ⚡⚡⚡ Networking tunnel: vxlan basic ⚡⚡⚡ Networking ipsec: basic netns - transport ⚡⚡⚡ Networking ipsec: basic netns - tunnel ⚡⚡⚡ Libkcapi AF_ALG test ⚡⚡⚡ trace: ftrace/tracer 🚧 ⚡⚡⚡ CIFS Connectathon 🚧 ⚡⚡⚡ POSIX pjd-fstest suites 🚧 ⚡⚡⚡ jvm - jcstress tests 🚧 ⚡⚡⚡ Memory function: kaslr 🚧 ⚡⚡⚡ Ethernet drivers sanity 🚧 ⚡⚡⚡ Networking firewall: basic netfilter test 🚧 ⚡⚡⚡ audit: audit testsuite test x86_64: Host 1: ⚡ Internal infrastructure issues prevented one or more tests (marked with ⚡⚡⚡) from running on this architecture. This is not the fault of the kernel that was tested. ⚡⚡⚡ Boot test ⚡⚡⚡ selinux-policy: serge-testsuite ⚡⚡⚡ storage: software RAID testing 🚧 ⚡⚡⚡ CPU: Frequency Driver Test 🚧 ⚡⚡⚡ CPU: Idle Test 🚧 ⚡⚡⚡ xfstests - ext4 🚧 ⚡⚡⚡ xfstests - xfs 🚧 ⚡⚡⚡ xfstests - btrfs 🚧 ⚡⚡⚡ xfstests - nfsv4.2 🚧 ⚡⚡⚡ xfstests - cifsv3.11 🚧 ⚡⚡⚡ IPMI driver test 🚧 ⚡⚡⚡ IPMItool loop stress test 🚧 ⚡⚡⚡ power-management: cpupower/sanity test 🚧 ⚡⚡⚡ Storage blktests 🚧 ⚡⚡⚡ Storage block - filesystem fio test 🚧 ⚡⚡⚡ Storage block - queue scheduler test 🚧 ⚡⚡⚡ Storage nvme - tcp 🚧 ⚡⚡⚡ Storage: swraid mdadm raid_module test 🚧 ⚡⚡⚡ stress: stress-ng Test sources: https://gitlab.com/cki-project/kernel-tests 💚 Pull requests are welcome for new tests or improvements to existing tests! Aborted tests ------------- Tests that didn't complete running successfully are marked with ⚡⚡⚡. If this was caused by an infrastructure issue, we try to mark that explicitly in the report. Waived tests ------------ If the test run included waived tests, they are marked with 🚧. Such tests are executed but their results are not taken into account. Tests are waived when their results are not reliable enough, e.g. when they're just introduced or are being fixed. Testing timeout --------------- We aim to provide a report within reasonable timeframe. Tests that haven't finished running yet are marked with ⏱.

4 years, 5 months

1
0
0 0

Re: [PATCH v2 1/1] s390/vfio-ap: fix circular lockdep when setting/clearing crypto masks

by Tony Krowiak

On 2/25/21 8:53 AM, Tony Krowiak wrote: > > > On 2/25/21 6:28 AM, Halil Pasic wrote: >> On Wed, 24 Feb 2021 22:28:50 -0500 >> Tony Krowiak<akrowiak(a)linux.ibm.com> wrote: >> >>>>> static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev) >>>>> { >>>>> - kvm_arch_crypto_clear_masks(matrix_mdev->kvm); >>>>> - matrix_mdev->kvm->arch.crypto.pqap_hook = NULL; >>>>> - vfio_ap_mdev_reset_queues(matrix_mdev->mdev); >>>>> - kvm_put_kvm(matrix_mdev->kvm); >>>>> - matrix_mdev->kvm = NULL; >>>>> + struct kvm *kvm; >>>>> + >>>>> + if (matrix_mdev->kvm) { >>>>> + kvm = matrix_mdev->kvm; >>>>> + kvm_get_kvm(kvm); >>>>> + matrix_mdev->kvm = NULL; >>>> I think if there were two threads dong the unset in parallel, one >>>> of them could bail out and carry on before the cleanup is done. But >>>> since nothing much happens in release after that, I don't see an >>>> immediate problem. >>>> >>>> Another thing to consider is, that setting ->kvm to NULL arms >>>> vfio_ap_mdev_remove()... >>> I'm not entirely sure what you mean by this, but my >>> assumption is that you are talking about the check >>> for matrix_mdev->kvm != NULL at the start of >>> that function. >> Yes I was talking about the check >> >> static int vfio_ap_mdev_remove(struct mdev_device *mdev) >> { >> struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >> >> if (matrix_mdev->kvm) >> return -EBUSY; >> ... >> kfree(matrix_mdev); >> ... >> } >> >> As you see, we bail out if kvm is still set, otherwise we clean up the >> matrix_mdev which includes kfree-ing it. And vfio_ap_mdev_remove() is >> initiated via the sysfs, i.e. can be initiated at any time. If we were >> to free matrix_mdev in mdev_remove() and then carry on with kvm_unset() >> with mutex_lock(&matrix_dev->lock); that would be bad. > > I agree. > >> >>> The reason >>> matrix_mdev->kvm is set to NULL before giving up >>> the matrix_dev->lock is so that functions that check >>> for the presence of the matrix_mdev->kvm pointer, >>> such as assign_adapter_store() - will exit if they get >>> control while the masks are being cleared. >> I disagree! >> >> static ssize_t assign_adapter_store(struct device *dev, >> struct device_attribute *attr, >> const char *buf, size_t count) >> { >> int ret; >> unsigned long apid; >> struct mdev_device *mdev = mdev_from_dev(dev); >> struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >> >> /* If the guest is running, disallow assignment of adapter */ >> if (matrix_mdev->kvm) >> return -EBUSY; >> >> We bail out when kvm != NULL, so having it set to NULL while the >> mask are being cleared will make these not bail out. > > You are correct, I am an idiot. > >>> So what we have >>> here is a catch-22; in other words, we have the case >>> you pointed out above and the cases related to >>> assigning/unassigning adapters, domains and >>> control domains which should exit when a guest >>> is running. >> See above. > > Ditto. > >>> I may have an idea to resolve this. Suppose we add: >>> >>> struct ap_matrix_mdev { >>> ... >>> bool kvm_busy; >>> ... >>> } >>> >>> This flag will be set to true at the start of both the >>> vfio_ap_mdev_set_kvm() and vfio_ap_mdev_unset_kvm() >>> and set to false at the end. The assignment/unassignment >>> and remove callback functions can test this flag and >>> return -EBUSY if the flag is true. That will preclude assigning >>> or unassigning adapters, domains and control domains when >>> the KVM pointer is being set/unset. Likewise, removal of the >>> mediated device will also be prevented while the KVM pointer >>> is being set/unset. >>> >>> In the case of the PQAP handler function, it can wait for the >>> set/unset of the KVM pointer as follows: >>> >>> /while (matrix_mdev->kvm_busy) {// >>> // mutex_unlock(&matrix_dev->lock);// >>> // msleep(100);// >>> // mutex_lock(&matrix_dev->lock);// >>> //}// >>> // >>> //if (!matrix_mdev->kvm)// >>> // goto out_unlock; >>> >>> /What say you? >>> // >> I'm not sure. Since I disagree with your analysis above it is difficult >> to deal with the conclusion. I'm not against decoupling the tracking of >> the state of the mdev_matrix device from the value of the kvm pointer. I >> think we should first get a common understanding of the problem, before >> we proceed to the solution. > > Regardless of my brain fog regarding the testing of the > matrix_mdev->kvm pointer, I stand by what I stated > in the paragraphs just before the code snippet. > > The problem is there are 10 functions that depend upon > the value of the matrix_mdev->kvm pointer that can get > control while the pointer is being set/unset and the > matrix_dev->lock is given up to set/clear the masks: * vfio_ap_irq_enable: called by handle_pqap() when AQIC is intercepted * vfio_ap_irq_disable: called by handle_pqap() when AQIC is intercepted * assign_adapter_store: sysfs * unassign_adapter_store: sysfs * assign_domain_store: sysfs * unassign_domain_store: sysfs * assign__control_domain_store: sysfs * unassign_control_domain_store: sysfs * vfio_ap_mdev_remove: sysfs * vfio_ap_mdev_release: mdev fd closed by userspace (i.e., qemu)If we add the proposed flag to indicate when the matrix_mdev->kvm > pointer is in flux, then we can check that before allowing the functions > in the list above to proceed. > >> Regards, >> Halil >

4 years, 5 months

2
2
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror