linux-stable.git/drivers/dax, branch linux-5.10.y Linux kernel stable tree dax: Introduce alloc_dev_dax_id() 2023-07-27T06:44:00+00:00 Dan Williams dan.j.williams@intel.com 2023-06-03T06:14:05+00:00 557e528255d5f5ea87b0db91969f317ebf4367f2 [ Upstream commit 70aab281e18c68a1284bc387de127c2fc0bed3f8 ] The reference counting of dax_region objects is needlessly complicated, has lead to confusion [1], and has hidden a bug [2]. Towards cleaning up that mess introduce alloc_dev_dax_id() to minimize the holding of a dax_region reference to only what dev_dax_release() needs, the dax_region->ida. Part of the reason for the mess was the design to dereference a dax_region in all cases in free_dev_dax_id() even if the id was statically assigned by the upper level dax_region driver. Remove the need to call "is_static(dax_region)" by tracking whether the id is dynamic directly in the dev_dax instance itself. With that flag the dax_region pinning and release per dev_dax instance can move to alloc_dev_dax_id() and free_dev_dax_id() respectively. A follow-on cleanup address the unnecessary references in the dax_region setup and drivers. Fixes: 0f3da14a4f05 ("device-dax: introduce 'seed' devices") Link: http://lore.kernel.org/r/20221203095858.612027-1-liuyongqiang13@huawei.com [1] Link: http://lore.kernel.org/r/3cf0890b-4eb0-e70e-cd9c-2ecc3d496263@hpe.com [2] Reported-by: Yongqiang Liu <liuyongqiang13@huawei.com> Reported-by: Paul Cassella <cassella@hpe.com> Reported-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/168577284563.1672036.13493034988900989554.stgit@dwillia2-xfh.jf.intel.com Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 70aab281e18c68a1284bc387de127c2fc0bed3f8 ]

The reference counting of dax_region objects is needlessly complicated,
has lead to confusion [1], and has hidden a bug [2]. Towards cleaning up
that mess introduce alloc_dev_dax_id() to minimize the holding of a
dax_region reference to only what dev_dax_release() needs, the
dax_region->ida.

Part of the reason for the mess was the design to dereference a
dax_region in all cases in free_dev_dax_id() even if the id was
statically assigned by the upper level dax_region driver. Remove the
need to call "is_static(dax_region)" by tracking whether the id is
dynamic directly in the dev_dax instance itself.

With that flag the dax_region pinning and release per dev_dax instance
can move to alloc_dev_dax_id() and free_dev_dax_id() respectively.

A follow-on cleanup address the unnecessary references in the dax_region
setup and drivers.

Fixes: 0f3da14a4f05 ("device-dax: introduce 'seed' devices")
Link: http://lore.kernel.org/r/20221203095858.612027-1-liuyongqiang13@huawei.com [1]
Link: http://lore.kernel.org/r/3cf0890b-4eb0-e70e-cd9c-2ecc3d496263@hpe.com [2]
Reported-by: Yongqiang Liu <liuyongqiang13@huawei.com>
Reported-by: Paul Cassella <cassella@hpe.com>
Reported-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/168577284563.1672036.13493034988900989554.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dax: Fix dax_mapping_release() use after free 2023-07-27T06:44:00+00:00 Dan Williams dan.j.williams@intel.com 2023-06-03T06:13:54+00:00 94a85474f5e3e518bdbf8c9f51cb343d734a04f7 [ Upstream commit 6d24b170a9db0456f577b1ab01226a2254c016a8 ] A CONFIG_DEBUG_KOBJECT_RELEASE test of removing a device-dax region provider (like modprobe -r dax_hmem) yields: kobject: 'mapping0' (ffff93eb460e8800): kobject_release, parent 0000000000000000 (delayed 2000) [..] DEBUG_LOCKS_WARN_ON(1) WARNING: CPU: 23 PID: 282 at kernel/locking/lockdep.c:232 __lock_acquire+0x9fc/0x2260 [..] RIP: 0010:__lock_acquire+0x9fc/0x2260 [..] Call Trace: <TASK> [..] lock_acquire+0xd4/0x2c0 ? ida_free+0x62/0x130 _raw_spin_lock_irqsave+0x47/0x70 ? ida_free+0x62/0x130 ida_free+0x62/0x130 dax_mapping_release+0x1f/0x30 device_release+0x36/0x90 kobject_delayed_cleanup+0x46/0x150 Due to attempting ida_free() on an ida object that has already been freed. Devices typically only hold a reference on their parent while registered. If a child needs a parent object to complete its release it needs to hold a reference that it drops from its release callback. Arrange for a dax_mapping to pin its parent dev_dax instance until dax_mapping_release(). Fixes: 0b07ce872a9e ("device-dax: introduce 'mapping' devices") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Link: https://lore.kernel.org/r/168577283412.1672036.16111545266174261446.stgit@dwillia2-xfh.jf.intel.com Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6d24b170a9db0456f577b1ab01226a2254c016a8 ]

A CONFIG_DEBUG_KOBJECT_RELEASE test of removing a device-dax region
provider (like modprobe -r dax_hmem) yields:

 kobject: 'mapping0' (ffff93eb460e8800): kobject_release, parent 0000000000000000 (delayed 2000)
 [..]
 DEBUG_LOCKS_WARN_ON(1)
 WARNING: CPU: 23 PID: 282 at kernel/locking/lockdep.c:232 __lock_acquire+0x9fc/0x2260
 [..]
 RIP: 0010:__lock_acquire+0x9fc/0x2260
 [..]
 Call Trace:
  <TASK>
 [..]
  lock_acquire+0xd4/0x2c0
  ? ida_free+0x62/0x130
  _raw_spin_lock_irqsave+0x47/0x70
  ? ida_free+0x62/0x130
  ida_free+0x62/0x130
  dax_mapping_release+0x1f/0x30
  device_release+0x36/0x90
  kobject_delayed_cleanup+0x46/0x150

Due to attempting ida_free() on an ida object that has already been
freed. Devices typically only hold a reference on their parent while
registered. If a child needs a parent object to complete its release it
needs to hold a reference that it drops from its release callback.
Arrange for a dax_mapping to pin its parent dev_dax instance until
dax_mapping_release().

Fixes: 0b07ce872a9e ("device-dax: introduce 'mapping' devices")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/168577283412.1672036.16111545266174261446.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dax/kmem: Fix leak of memory-hotplug resources 2023-03-11T15:40:04+00:00 Dan Williams dan.j.williams@intel.com 2023-02-16T08:36:02+00:00 cd4d3eab231006f6c174a2630f3158ee25c3fceb commit e686c32590f40bffc45f105c04c836ffad3e531a upstream. While experimenting with CXL region removal the following corruption of /proc/iomem appeared. Before: f010000000-f04fffffff : CXL Window 0 f010000000-f02fffffff : region4 f010000000-f02fffffff : dax4.0 f010000000-f02fffffff : System RAM (kmem) After (modprobe -r cxl_test): f010000000-f02fffffff : **redacted binary garbage** f010000000-f02fffffff : System RAM (kmem) ...and testing further the same is visible with persistent memory assigned to kmem: Before: 480000000-243fffffff : Persistent Memory 480000000-57e1fffff : namespace3.0 580000000-243fffffff : dax3.0 580000000-243fffffff : System RAM (kmem) After (ndctl disable-region all): 480000000-243fffffff : Persistent Memory 580000000-243fffffff : ***redacted binary garbage*** 580000000-243fffffff : System RAM (kmem) The corrupted data is from a use-after-free of the "dax4.0" and "dax3.0" resources, and it also shows that the "System RAM (kmem)" resource is not being removed. The bug does not appear after "modprobe -r kmem", it requires the parent of "dax4.0" and "dax3.0" to be removed which re-parents the leaked "System RAM (kmem)" instances. Those in turn reference the freed resource as a parent. First up for the fix is release_mem_region_adjustable() needs to reliably delete the resource inserted by add_memory_driver_managed(). That is thwarted by a check for IORESOURCE_SYSRAM that predates the dax/kmem driver, from commit: 65c78784135f ("kernel, resource: check for IORESOURCE_SYSRAM in release_mem_region_adjustable") That appears to be working around the behavior of HMM's "MEMORY_DEVICE_PUBLIC" facility that has since been deleted. With that check removed the "System RAM (kmem)" resource gets removed, but corruption still occurs occasionally because the "dax" resource is not reliably removed. The dax range information is freed before the device is unregistered, so the driver can not reliably recall (another use after free) what it is meant to release. Lastly if that use after free got lucky, the driver was covering up the leak of "System RAM (kmem)" due to its use of release_resource() which detaches, but does not free, child resources. The switch to remove_resource() forces remove_memory() to be responsible for the deletion of the resource added by add_memory_driver_managed(). Fixes: c2f3011ee697 ("device-dax: add an allocation interface for device-dax instances") Cc: <stable@vger.kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Vishal Verma <vishal.l.verma@intel.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/167653656244.3147810.5705900882794040229.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e686c32590f40bffc45f105c04c836ffad3e531a upstream.

While experimenting with CXL region removal the following corruption of
/proc/iomem appeared.

Before:
f010000000-f04fffffff : CXL Window 0
  f010000000-f02fffffff : region4
    f010000000-f02fffffff : dax4.0
      f010000000-f02fffffff : System RAM (kmem)

After (modprobe -r cxl_test):
f010000000-f02fffffff : **redacted binary garbage**
  f010000000-f02fffffff : System RAM (kmem)

...and testing further the same is visible with persistent memory
assigned to kmem:

Before:
480000000-243fffffff : Persistent Memory
  480000000-57e1fffff : namespace3.0
  580000000-243fffffff : dax3.0
    580000000-243fffffff : System RAM (kmem)

After (ndctl disable-region all):
480000000-243fffffff : Persistent Memory
  580000000-243fffffff : ***redacted binary garbage***
    580000000-243fffffff : System RAM (kmem)

The corrupted data is from a use-after-free of the "dax4.0" and "dax3.0"
resources, and it also shows that the "System RAM (kmem)" resource is
not being removed. The bug does not appear after "modprobe -r kmem", it
requires the parent of "dax4.0" and "dax3.0" to be removed which
re-parents the leaked "System RAM (kmem)" instances. Those in turn
reference the freed resource as a parent.

First up for the fix is release_mem_region_adjustable() needs to
reliably delete the resource inserted by add_memory_driver_managed().
That is thwarted by a check for IORESOURCE_SYSRAM that predates the
dax/kmem driver, from commit:

65c78784135f ("kernel, resource: check for IORESOURCE_SYSRAM in release_mem_region_adjustable")

That appears to be working around the behavior of HMM's
"MEMORY_DEVICE_PUBLIC" facility that has since been deleted. With that
check removed the "System RAM (kmem)" resource gets removed, but
corruption still occurs occasionally because the "dax" resource is not
reliably removed.

The dax range information is freed before the device is unregistered, so
the driver can not reliably recall (another use after free) what it is
meant to release. Lastly if that use after free got lucky, the driver
was covering up the leak of "System RAM (kmem)" due to its use of
release_resource() which detaches, but does not free, child resources.
The switch to remove_resource() forces remove_memory() to be responsible
for the deletion of the resource added by add_memory_driver_managed().

Fixes: c2f3011ee697 ("device-dax: add an allocation interface for device-dax instances")
Cc: <stable@vger.kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/167653656244.3147810.5705900882794040229.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
devdax: Fix soft-reservation memory description 2022-09-28T09:10:41+00:00 Dan Williams dan.j.williams@intel.com 2022-09-23T22:05:56+00:00 25117265152ebc6d4f89b1a8ea6e336ea1e19a35 commit 67feaba413ec68daf4124e9870878899b4ed9a0e upstream. The "hmem" platform-devices that are created to represent the platform-advertised "Soft Reserved" memory ranges end up inserting a resource that causes the iomem_resource tree to look like this: 340000000-43fffffff : hmem.0 340000000-43fffffff : Soft Reserved 340000000-43fffffff : dax0.0 This is because insert_resource() reparents ranges when they completely intersect an existing range. This matters because code that uses region_intersects() to scan for a given IORES_DESC will only check that top-level 'hmem.0' resource and not the 'Soft Reserved' descendant. So, to support EINJ (via einj_error_inject()) to inject errors into memory hosted by a dax-device, be sure to describe the memory as IORES_DESC_SOFT_RESERVED. This is a follow-on to: commit b13a3e5fd40b ("ACPI: APEI: Fix _EINJ vs EFI_MEMORY_SP") ...that fixed EINJ support for "Soft Reserved" ranges in the first instance. Fixes: 262b45ae3ab4 ("x86/efi: EFI soft reservation to E820 enumeration") Reported-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com> Tested-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com> Cc: <stable@vger.kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Omar Avelar <omar.avelar@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mark Gross <markgross@kernel.org> Link: https://lore.kernel.org/r/166397075670.389916.7435722208896316387.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 67feaba413ec68daf4124e9870878899b4ed9a0e upstream.

The "hmem" platform-devices that are created to represent the
platform-advertised "Soft Reserved" memory ranges end up inserting a
resource that causes the iomem_resource tree to look like this:

340000000-43fffffff : hmem.0
  340000000-43fffffff : Soft Reserved
    340000000-43fffffff : dax0.0

This is because insert_resource() reparents ranges when they completely
intersect an existing range.

This matters because code that uses region_intersects() to scan for a
given IORES_DESC will only check that top-level 'hmem.0' resource and
not the 'Soft Reserved' descendant.

So, to support EINJ (via einj_error_inject()) to inject errors into
memory hosted by a dax-device, be sure to describe the memory as
IORES_DESC_SOFT_RESERVED. This is a follow-on to:

commit b13a3e5fd40b ("ACPI: APEI: Fix _EINJ vs EFI_MEMORY_SP")

...that fixed EINJ support for "Soft Reserved" ranges in the first
instance.

Fixes: 262b45ae3ab4 ("x86/efi: EFI soft reservation to E820 enumeration")
Reported-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com>
Tested-by: Ricardo Sandoval Torres <ricardo.sandoval.torres@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Omar Avelar <omar.avelar@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mark Gross <markgross@kernel.org>
Link: https://lore.kernel.org/r/166397075670.389916.7435722208896316387.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dax: make sure inodes are flushed before destroy cache 2022-04-08T12:40:16+00:00 Tong Zhang ztong0001@gmail.com 2022-02-12T07:11:11+00:00 ec376f5c11c88c0215d173599db8449cd4196759 [ Upstream commit a7e8de822e0b1979f08767c751f6c8a9c1d4ad86 ] A bug can be triggered by following command $ modprobe nd_pmem && modprobe -r nd_pmem [ 10.060014] BUG dax_cache (Not tainted): Objects remaining in dax_cache on __kmem_cache_shutdown() [ 10.060938] Slab 0x0000000085b729ac objects=9 used=1 fp=0x000000004f5ae469 flags=0x200000000010200(slab|head|node) [ 10.062433] Call Trace: [ 10.062673] dump_stack_lvl+0x34/0x44 [ 10.062865] slab_err+0x90/0xd0 [ 10.063619] __kmem_cache_shutdown+0x13b/0x2f0 [ 10.063848] kmem_cache_destroy+0x4a/0x110 [ 10.064058] __x64_sys_delete_module+0x265/0x300 This is caused by dax_fs_exit() not flushing inodes before destroy cache. To fix this issue, call rcu_barrier() before destroy cache. Signed-off-by: Tong Zhang <ztong0001@gmail.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220212071111.148575-1-ztong0001@gmail.com Fixes: 7b6be8444e0f ("dax: refactor dax-fs into a generic provider of 'struct dax_device' instances") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a7e8de822e0b1979f08767c751f6c8a9c1d4ad86 ]

A bug can be triggered by following command

$ modprobe nd_pmem && modprobe -r nd_pmem

[   10.060014] BUG dax_cache (Not tainted): Objects remaining in dax_cache on __kmem_cache_shutdown()
[   10.060938] Slab 0x0000000085b729ac objects=9 used=1 fp=0x000000004f5ae469 flags=0x200000000010200(slab|head|node)
[   10.062433] Call Trace:
[   10.062673]  dump_stack_lvl+0x34/0x44
[   10.062865]  slab_err+0x90/0xd0
[   10.063619]  __kmem_cache_shutdown+0x13b/0x2f0
[   10.063848]  kmem_cache_destroy+0x4a/0x110
[   10.064058]  __x64_sys_delete_module+0x265/0x300

This is caused by dax_fs_exit() not flushing inodes before destroy cache.
To fix this issue, call rcu_barrier() before destroy cache.

Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220212071111.148575-1-ztong0001@gmail.com
Fixes: 7b6be8444e0f ("dax: refactor dax-fs into a generic provider of 'struct dax_device' instances")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
device-dax: Fix default return code of range_parse() 2021-03-04T10:38:15+00:00 Shiyang Ruan ruansy.fnst@cn.fujitsu.com 2021-01-26T02:13:31+00:00 fc22917f48ee61eebfc462de92a685b9f508bddc [ Upstream commit 7323fb22f05ff1d20498d267828870a5fbbaebd6 ] The return value of range_parse() indicates the size when it is positive. The error code should be negative. Signed-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Link: https://lore.kernel.org/r/20210126021331.1059933-1-ruansy.fnst@cn.fujitsu.com Reported-by: Zhang Qilong <zhangqilong3@huawei.com> Fixes: 8490e2e25b5a ("device-dax: add a range mapping allocation attribute") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 7323fb22f05ff1d20498d267828870a5fbbaebd6 ]

The return value of range_parse() indicates the size when it is
positive.  The error code should be negative.

Signed-off-by: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20210126021331.1059933-1-ruansy.fnst@cn.fujitsu.com
Reported-by: Zhang Qilong <zhangqilong3@huawei.com>
Fixes: 8490e2e25b5a ("device-dax: add a range mapping allocation attribute")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
device-dax: Fix range release 2021-01-06T13:56:56+00:00 Dan Williams dan.j.williams@intel.com 2020-12-19T02:41:41+00:00 12d377b93eef28af70219fcc83eeb637a1ff6853 [ Upstream commit 6268d7da4d192af339f4d688942b9ccb45a65e04 ] There are multiple locations that open-code the release of the last range in a device-dax instance. Consolidate this into a new dev_dax_trim_range() helper. This also addresses a kmemleak report: # cat /sys/kernel/debug/kmemleak [..] unreferenced object 0xffff976bd46f6240 (size 64): comm "ndctl", pid 23556, jiffies 4299514316 (age 5406.733s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 20 c3 37 00 00 00 .......... .7... ff ff ff 7f 38 00 00 00 00 00 00 00 00 00 00 00 ....8........... backtrace: [<00000000064003cf>] __kmalloc_track_caller+0x136/0x379 [<00000000d85e3c52>] krealloc+0x67/0x92 [<00000000d7d3ba8a>] __alloc_dev_dax_range+0x73/0x25c [<0000000027d58626>] devm_create_dev_dax+0x27d/0x416 [<00000000434abd43>] __dax_pmem_probe+0x1c9/0x1000 [dax_pmem_core] [<0000000083726c1c>] dax_pmem_probe+0x10/0x1f [dax_pmem] [<00000000b5f2319c>] nvdimm_bus_probe+0x9d/0x340 [libnvdimm] [<00000000c055e544>] really_probe+0x230/0x48d [<000000006cabd38e>] driver_probe_device+0x122/0x13b [<0000000029c7b95a>] device_driver_attach+0x5b/0x60 [<0000000053e5659b>] bind_store+0xb7/0xc3 [<00000000d3bdaadc>] drv_attr_store+0x27/0x31 [<00000000949069c5>] sysfs_kf_write+0x4a/0x57 [<000000004a8b5adf>] kernfs_fop_write+0x150/0x1e5 [<00000000bded60f0>] __vfs_write+0x1b/0x34 [<00000000b92900f0>] vfs_write+0xd8/0x1d1 Reported-by: Jane Chu <jane.chu@oracle.com> Cc: Zhen Lei <thunder.leizhen@huawei.com> Link: https://lore.kernel.org/r/160834570161.1791850.14911670304441510419.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 6268d7da4d192af339f4d688942b9ccb45a65e04 ]

There are multiple locations that open-code the release of the last
range in a device-dax instance. Consolidate this into a new
dev_dax_trim_range() helper.

This also addresses a kmemleak report:

# cat /sys/kernel/debug/kmemleak
[..]
unreferenced object 0xffff976bd46f6240 (size 64):
   comm "ndctl", pid 23556, jiffies 4299514316 (age 5406.733s)
   hex dump (first 32 bytes):
     00 00 00 00 00 00 00 00 00 00 20 c3 37 00 00 00  .......... .7...
     ff ff ff 7f 38 00 00 00 00 00 00 00 00 00 00 00  ....8...........
   backtrace:
     [<00000000064003cf>] __kmalloc_track_caller+0x136/0x379
     [<00000000d85e3c52>] krealloc+0x67/0x92
     [<00000000d7d3ba8a>] __alloc_dev_dax_range+0x73/0x25c
     [<0000000027d58626>] devm_create_dev_dax+0x27d/0x416
     [<00000000434abd43>] __dax_pmem_probe+0x1c9/0x1000 [dax_pmem_core]
     [<0000000083726c1c>] dax_pmem_probe+0x10/0x1f [dax_pmem]
     [<00000000b5f2319c>] nvdimm_bus_probe+0x9d/0x340 [libnvdimm]
     [<00000000c055e544>] really_probe+0x230/0x48d
     [<000000006cabd38e>] driver_probe_device+0x122/0x13b
     [<0000000029c7b95a>] device_driver_attach+0x5b/0x60
     [<0000000053e5659b>] bind_store+0xb7/0xc3
     [<00000000d3bdaadc>] drv_attr_store+0x27/0x31
     [<00000000949069c5>] sysfs_kf_write+0x4a/0x57
     [<000000004a8b5adf>] kernfs_fop_write+0x150/0x1e5
     [<00000000bded60f0>] __vfs_write+0x1b/0x34
     [<00000000b92900f0>] vfs_write+0xd8/0x1d1

Reported-by: Jane Chu <jane.chu@oracle.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Link: https://lore.kernel.org/r/160834570161.1791850.14911670304441510419.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
device-dax/core: Fix memory leak when rmmod dax.ko 2020-12-30T10:54:26+00:00 Wang Hai wanghai38@huawei.com 2020-12-01T13:59:29+00:00 224adad2c975ec706ba3c451ce8e10f1d3d9806d commit 1aa574312518ef1d60d2dc62d58f7021db3b163a upstream. When I repeatedly modprobe and rmmod dax.ko, kmemleak report a memory leak as follows: unreferenced object 0xffff9a5588c05088 (size 8): comm "modprobe", pid 261, jiffies 4294693644 (age 42.063s) ... backtrace: [<00000000e007ced0>] kstrdup+0x35/0x70 [<000000002ae73897>] kstrdup_const+0x3d/0x50 [<000000002b00c9c3>] kvasprintf_const+0xbc/0xf0 [<000000008023282f>] kobject_set_name_vargs+0x3b/0xd0 [<00000000d2cbaa4e>] kobject_set_name+0x62/0x90 [<00000000202e7a22>] bus_register+0x7f/0x2b0 [<000000000b77792c>] 0xffffffffc02840f7 [<000000002d5be5ac>] 0xffffffffc02840b4 [<00000000dcafb7cd>] do_one_initcall+0x58/0x240 [<00000000049fe480>] do_init_module+0x56/0x1e2 [<0000000022671491>] load_module+0x2517/0x2840 [<000000001a2201cb>] __do_sys_finit_module+0x9c/0xe0 [<000000003eb304e7>] do_syscall_64+0x33/0x40 [<0000000051c5fd06>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 When rmmod dax is executed, dax_bus_exit() is missing. This patch can fix this bug. Fixes: 9567da0b408a ("device-dax: Introduce bus + driver model") Cc: <stable@vger.kernel.org> Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wang Hai <wanghai38@huawei.com> Link: https://lore.kernel.org/r/20201201135929.66530-1-wanghai38@huawei.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1aa574312518ef1d60d2dc62d58f7021db3b163a upstream.

When I repeatedly modprobe and rmmod dax.ko, kmemleak report a
memory leak as follows:

unreferenced object 0xffff9a5588c05088 (size 8):
  comm "modprobe", pid 261, jiffies 4294693644 (age 42.063s)
...
  backtrace:
    [<00000000e007ced0>] kstrdup+0x35/0x70
    [<000000002ae73897>] kstrdup_const+0x3d/0x50
    [<000000002b00c9c3>] kvasprintf_const+0xbc/0xf0
    [<000000008023282f>] kobject_set_name_vargs+0x3b/0xd0
    [<00000000d2cbaa4e>] kobject_set_name+0x62/0x90
    [<00000000202e7a22>] bus_register+0x7f/0x2b0
    [<000000000b77792c>] 0xffffffffc02840f7
    [<000000002d5be5ac>] 0xffffffffc02840b4
    [<00000000dcafb7cd>] do_one_initcall+0x58/0x240
    [<00000000049fe480>] do_init_module+0x56/0x1e2
    [<0000000022671491>] load_module+0x2517/0x2840
    [<000000001a2201cb>] __do_sys_finit_module+0x9c/0xe0
    [<000000003eb304e7>] do_syscall_64+0x33/0x40
    [<0000000051c5fd06>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

When rmmod dax is executed, dax_bus_exit() is missing. This patch
can fix this bug.

Fixes: 9567da0b408a ("device-dax: Introduce bus + driver model")
Cc: <stable@vger.kernel.org>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Link: https://lore.kernel.org/r/20201201135929.66530-1-wanghai38@huawei.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports 2020-11-22T18:48:22+00:00 Dan Williams dan.j.williams@intel.com 2020-11-22T06:17:05+00:00 a927bd6ba952d13c52b8b385030943032f659a3e The core-mm has a default __weak implementation of phys_to_target_node() to mirror the weak definition of memory_add_physaddr_to_nid(). That symbol is exported for modules. However, while the export in mm/memory_hotplug.c exported the symbol in the configuration cases of: CONFIG_NUMA_KEEP_MEMINFO=y CONFIG_MEMORY_HOTPLUG=y ...and: CONFIG_NUMA_KEEP_MEMINFO=n CONFIG_MEMORY_HOTPLUG=y ...it failed to export the symbol in the case of: CONFIG_NUMA_KEEP_MEMINFO=y CONFIG_MEMORY_HOTPLUG=n Not only is that broken, but Christoph points out that the kernel should not be exporting any __weak symbol, which means that memory_add_physaddr_to_nid() example that phys_to_target_node() copied is broken too. Rework the definition of phys_to_target_node() and memory_add_physaddr_to_nid() to not require weak symbols. Move to the common arch override design-pattern of an asm header defining a symbol to replace the default implementation. The only common header that all memory_add_physaddr_to_nid() producing architectures implement is asm/sparsemem.h. In fact, powerpc already defines its memory_add_physaddr_to_nid() helper in sparsemem.h. Double-down on that observation and define phys_to_target_node() where necessary in asm/sparsemem.h. An alternate consideration that was discarded was to put this override in asm/numa.h, but that entangles with the definition of MAX_NUMNODES relative to the inclusion of linux/nodemask.h, and requires powerpc to grow a new header. The dependency on NUMA_KEEP_MEMINFO for DEV_DAX_HMEM_DEVICES is invalid now that the symbol is properly exported / stubbed in all combinations of CONFIG_NUMA_KEEP_MEMINFO and CONFIG_MEMORY_HOTPLUG. [dan.j.williams@intel.com: v4] Link: https://lkml.kernel.org/r/160461461867.1505359.5301571728749534585.stgit@dwillia2-desk3.amr.corp.intel.com [dan.j.williams@intel.com: powerpc: fix create_section_mapping compile warning] Link: https://lkml.kernel.org/r/160558386174.2948926.2740149041249041764.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: a035b6bf863e ("mm/memory_hotplug: introduce default phys_to_target_node() implementation") Reported-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
The core-mm has a default __weak implementation of phys_to_target_node()
to mirror the weak definition of memory_add_physaddr_to_nid().  That
symbol is exported for modules.  However, while the export in
mm/memory_hotplug.c exported the symbol in the configuration cases of:

	CONFIG_NUMA_KEEP_MEMINFO=y
	CONFIG_MEMORY_HOTPLUG=y

...and:

	CONFIG_NUMA_KEEP_MEMINFO=n
	CONFIG_MEMORY_HOTPLUG=y

...it failed to export the symbol in the case of:

	CONFIG_NUMA_KEEP_MEMINFO=y
	CONFIG_MEMORY_HOTPLUG=n

Not only is that broken, but Christoph points out that the kernel should
not be exporting any __weak symbol, which means that
memory_add_physaddr_to_nid() example that phys_to_target_node() copied
is broken too.

Rework the definition of phys_to_target_node() and
memory_add_physaddr_to_nid() to not require weak symbols.  Move to the
common arch override design-pattern of an asm header defining a symbol
to replace the default implementation.

The only common header that all memory_add_physaddr_to_nid() producing
architectures implement is asm/sparsemem.h.  In fact, powerpc already
defines its memory_add_physaddr_to_nid() helper in sparsemem.h.
Double-down on that observation and define phys_to_target_node() where
necessary in asm/sparsemem.h.  An alternate consideration that was
discarded was to put this override in asm/numa.h, but that entangles
with the definition of MAX_NUMNODES relative to the inclusion of
linux/nodemask.h, and requires powerpc to grow a new header.

The dependency on NUMA_KEEP_MEMINFO for DEV_DAX_HMEM_DEVICES is invalid
now that the symbol is properly exported / stubbed in all combinations
of CONFIG_NUMA_KEEP_MEMINFO and CONFIG_MEMORY_HOTPLUG.

[dan.j.williams@intel.com: v4]
  Link: https://lkml.kernel.org/r/160461461867.1505359.5301571728749534585.stgit@dwillia2-desk3.amr.corp.intel.com
[dan.j.williams@intel.com: powerpc: fix create_section_mapping compile warning]
  Link: https://lkml.kernel.org/r/160558386174.2948926.2740149041249041764.stgit@dwillia2-desk3.amr.corp.intel.com

Fixes: a035b6bf863e ("mm/memory_hotplug: introduce default phys_to_target_node() implementation")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lkml.kernel.org/r/160447639846.1133764.7044090803980177548.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'fuse-update-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse 2020-10-19T21:28:30+00:00 Linus Torvalds torvalds@linux-foundation.org 2020-10-19T21:28:30+00:00 694565356c2e06224d94774a42709cc8dfab49ee Pull fuse updates from Miklos Szeredi: - Support directly accessing host page cache from virtiofs. This can improve I/O performance for various workloads, as well as reducing the memory requirement by eliminating double caching. Thanks to Vivek Goyal for doing most of the work on this. - Allow automatic submounting inside virtiofs. This allows unique st_dev/ st_ino values to be assigned inside the guest to files residing on different filesystems on the host. Thanks to Max Reitz for the patches. - Fix an old use after free bug found by Pradeep P V K. * tag 'fuse-update-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (25 commits) virtiofs: calculate number of scatter-gather elements accurately fuse: connection remove fix fuse: implement crossmounts fuse: Allow fuse_fill_super_common() for submounts fuse: split fuse_mount off of fuse_conn fuse: drop fuse_conn parameter where possible fuse: store fuse_conn in fuse_req fuse: add submount support to <uapi/linux/fuse.h> fuse: fix page dereference after free virtiofs: add logic to free up a memory range virtiofs: maintain a list of busy elements virtiofs: serialize truncate/punch_hole and dax fault path virtiofs: define dax address space operations virtiofs: add DAX mmap support virtiofs: implement dax read/write operations virtiofs: introduce setupmapping/removemapping commands virtiofs: implement FUSE_INIT map_alignment field virtiofs: keep a list of free dax memory ranges virtiofs: add a mount option to enable dax virtiofs: set up virtio_fs dax_device ... 
Pull fuse updates from Miklos Szeredi:

 - Support directly accessing host page cache from virtiofs. This can
   improve I/O performance for various workloads, as well as reducing
   the memory requirement by eliminating double caching. Thanks to Vivek
   Goyal for doing most of the work on this.

 - Allow automatic submounting inside virtiofs. This allows unique
   st_dev/ st_ino values to be assigned inside the guest to files
   residing on different filesystems on the host. Thanks to Max Reitz
   for the patches.

 - Fix an old use after free bug found by Pradeep P V K.

* tag 'fuse-update-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (25 commits)
  virtiofs: calculate number of scatter-gather elements accurately
  fuse: connection remove fix
  fuse: implement crossmounts
  fuse: Allow fuse_fill_super_common() for submounts
  fuse: split fuse_mount off of fuse_conn
  fuse: drop fuse_conn parameter where possible
  fuse: store fuse_conn in fuse_req
  fuse: add submount support to <uapi/linux/fuse.h>
  fuse: fix page dereference after free
  virtiofs: add logic to free up a memory range
  virtiofs: maintain a list of busy elements
  virtiofs: serialize truncate/punch_hole and dax fault path
  virtiofs: define dax address space operations
  virtiofs: add DAX mmap support
  virtiofs: implement dax read/write operations
  virtiofs: introduce setupmapping/removemapping commands
  virtiofs: implement FUSE_INIT map_alignment field
  virtiofs: keep a list of free dax memory ranges
  virtiofs: add a mount option to enable dax
  virtiofs: set up virtio_fs dax_device
  ...