mirror of
https://github.com/torvalds/linux.git
synced 2024-11-23 12:42:02 +00:00
c16d5a412e
160 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Dan Williams
|
e686c32590 |
dax/kmem: Fix leak of memory-hotplug resources
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:
|
||
Linus Torvalds
|
71a7507afb |
Driver Core changes for 6.2-rc1
Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems, OTHER than some merge issues with other trees that should be obvious when you hit them (block tree deletes a driver that this tree modifies, iommufd tree modifies code that this tree also touches). If there are merge problems with these trees, please let me know. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> -----BEGIN PGP SIGNATURE----- iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCY5wz3A8cZ3JlZ0Brcm9h aC5jb20ACgkQMUfUDdst+yks0ACeKYUlVgCsER8eYW+x18szFa2QTXgAn2h/VhZe 1Fp53boFaQkGBjl8mGF8 =v+FB -----END PGP SIGNATURE----- Merge tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems" * tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits) device property: Fix documentation for fwnode_get_next_parent() firmware_loader: fix up to_fw_sysfs() to preserve const usb.h: take advantage of container_of_const() device.h: move kobj_to_dev() to use container_of_const() container_of: add container_of_const() that preserves const-ness of the pointer driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion. driver core: fix up missed scsi/cxlflash class.devnode() conversion. driver core: fix up some missing class.devnode() conversions. driver core: make struct class.devnode() take a const * driver core: make struct class.dev_uevent() take a const * cacheinfo: Remove of_node_put() for fw_token device property: Add a blank line in Kconfig of tests device property: Rename goto label to be more precise device property: Move PROPERTY_ENTRY_BOOL() a bit down device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*() kernfs: fix all kernel-doc warnings and multiple typos driver core: pass a const * into of_device_uevent() kobject: kset_uevent_ops: make name() callback take a const * kobject: kset_uevent_ops: make filter() callback take a const * kobject: make kobject_namespace take a const * ... |
||
Ira Weiny
|
278294798a |
PCI: Allow drivers to request exclusive config regions
PCI config space access from user space has traditionally been unrestricted with writes being an understood risk for device operation. Unfortunately, device breakage or odd behavior from config writes lacks indicators that can leave driver writers confused when evaluating failures. This is especially true with the new PCIe Data Object Exchange (DOE) mailbox protocol where backdoor shenanigans from user space through things such as vendor defined protocols may affect device operation without complete breakage. A prior proposal restricted read and writes completely.[1] Greg and Bjorn pointed out that proposal is flawed for a couple of reasons. First, lspci should always be allowed and should not interfere with any device operation. Second, setpci is a valuable tool that is sometimes necessary and it should not be completely restricted.[2] Finally methods exist for full lock of device access if required. Even though access should not be restricted it would be nice for driver writers to be able to flag critical parts of the config space such that interference from user space can be detected. Introduce pci_request_config_region_exclusive() to mark exclusive config regions. Such regions trigger a warning and kernel taint if accessed via user space. Create pci_warn_once() to restrict the user from spamming the log. [1] https://lore.kernel.org/all/161663543465.1867664.5674061943008380442.stgit@dwillia2-desk3.amr.corp.intel.com/ [2] https://lore.kernel.org/all/YF8NGeGv9vYcMfTV@kroah.com/ Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20220926215711.2893286-2-ira.weiny@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
||
Andy Shevchenko
|
2a4e628570 |
resource: Replace printk(KERN_WARNING) by pr_warn(), printk() by pr_info()
Replace printk(KERN_WARNING) by pr_warn() and printk() by pr_info(). While at it, use %pa for the resource_size_t variables. With that, for the sake of consistency, introduce a temporary variable for the end address in iomem_map_sanity_check() like it's done in another function in the same module. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20221109155618.42276-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
||
|
Dan Williams
|
14b80582c4 |
resource: Introduce alloc_free_mem_region()
The core of devm_request_free_mem_region() is a helper that searches for free space in iomem_resource and performs __request_region_locked() on the result of that search. The policy choices of the implementation conform to what CONFIG_DEVICE_PRIVATE users want which is memory that is immediately marked busy, and a preference to search for the first-fit free range in descending order from the top of the physical address space. CXL has a need for a similar allocator, but with the following tweaks: 1/ Search for free space in ascending order 2/ Search for free space relative to a given CXL window 3/ 'insert' rather than 'request' the new resource given downstream drivers from the CXL Region driver (like the pmem or dax drivers) are responsible for request_mem_region() when they activate the memory range. Rework __request_free_mem_region() into get_free_mem_region() which takes a set of GFR_* (Get Free Region) flags to control the allocation policy (ascending vs descending), and "busy" policy (insert_resource() vs request_region()). As part of the consolidation of the legacy GFR_REQUEST_REGION case with the new default of just inserting a new resource into the free space some minor cleanups like not checking for NULL before calling devres_free() (which does its own check) is included. Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/linux-cxl/20220420143406.GY2120790@nvidia.com/ Cc: Matthew Wilcox <willy@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/165784333333.1758207.13703329337805274043.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
||
|
Dan Williams
|
974854ab07 |
cxl/acpi: Track CXL resources in iomem_resource
Recall that CXL capable address ranges, on ACPI platforms, are published in the CEDT.CFMWS (CXL Early Discovery Table: CXL Fixed Memory Window Structures). These windows represent both the actively mapped capacity and the potential address space that can be dynamically assigned to a new CXL decode configuration (region / interleave-set). CXL endpoints like DDR DIMMs can be mapped at any physical address including 0 and legacy ranges. There is an expectation and requirement that the /proc/iomem interface and the iomem_resource tree in the kernel reflect the full set of platform address ranges. I.e. that every address range that platform firmware and bus drivers enumerate be reflected as an iomem_resource entry. The hard requirement to do this for CXL arises from the fact that facilities like CONFIG_DEVICE_PRIVATE expect to be able to treat empty iomem_resource ranges as free for software to use as proxy address space. Without CXL publishing its potential address ranges in iomem_resource, the CONFIG_DEVICE_PRIVATE mechanism may inadvertently steal capacity reserved for runtime provisioning of new CXL regions. So, iomem_resource needs to know about both active and potential CXL resource ranges. The active CXL resources might already be reflected in iomem_resource as "System RAM". insert_resource_expand_to_fit() handles re-parenting "System RAM" underneath a CXL window. The "_expand_to_fit()" behavior handles cases where a CXL window is not a strict superset of an existing entry in the iomem_resource tree. The "_expand_to_fit()" behavior is acceptable from the perspective of resource allocation. The expansion happens because a conflicting resource range is already populated, which means the resource boundary expansion does not result in any additional free CXL address space being made available. CXL address space allocation is always bounded by the orginal unexpanded address range. However, the potential for expansion does mean that something like walk_iomem_res_desc(IORES_DESC_CXL...) can only return fuzzy answers on corner case platforms that cause the resource tree to expand a CXL window resource over a range that is not decoded by CXL. This would be an odd platform configuration, but if it becomes a problem in practice the CXL subsytem could just publish an API that returns definitive answers. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Christoph Hellwig <hch@lst.de> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/165784325943.1758207.5310344844375305118.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
||
Miaohe Lin
|
0cbcc92917 |
kernel/resource: fix kfree() of bootmem memory again
Since commit |
||
Muchun Song
|
359745d783 |
proc: remove PDE_DATA() completely
Remove PDE_DATA() completely and replace it with pde_data(). [akpm@linux-foundation.org: fix naming clash in drivers/nubus/proc.c] [akpm@linux-foundation.org: now fix it properly] Link: https://lkml.kernel.org/r/20211124081956.87711-2-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
David Hildenbrand
|
a9e7b8d4f6 |
kernel/resource: disallow access to exclusive system RAM regions
virtio-mem dynamically exposes memory inside a device memory region as
system RAM to Linux, coordinating with the hypervisor which parts are
actually "plugged" and consequently usable/accessible.
On the one hand, the virtio-mem driver adds/removes whole memory blocks,
creating/removing busy IORESOURCE_SYSTEM_RAM resources, on the other
hand, it logically (un)plugs memory inside added memory blocks,
dynamically either exposing them to the buddy or hiding them from the
buddy and marking them PG_offline.
In contrast to physical devices, like a DIMM, the virtio-mem driver is
required to actually make use of any of the device-provided memory,
because it performs the handshake with the hypervisor. virtio-mem
memory cannot simply be access via /dev/mem without a driver.
There is no safe way to:
a) Access plugged memory blocks via /dev/mem, as they might contain
unplugged holes or might get silently unplugged by the virtio-mem
driver and consequently turned inaccessible.
b) Access unplugged memory blocks via /dev/mem because the virtio-mem
driver is required to make them actually accessible first.
The virtio-spec states that unplugged memory blocks MUST NOT be written,
and only selected unplugged memory blocks MAY be read. We want to make
sure, this is the case in sane environments -- where the virtio-mem driver
was loaded.
We want to make sure that in a sane environment, nobody "accidentially"
accesses unplugged memory inside the device managed region. For example,
a user might spot a memory region in /proc/iomem and try accessing it via
/dev/mem via gdb or dumping it via something else. By the time the mmap()
happens, the memory might already have been removed by the virtio-mem
driver silently: the mmap() would succeeed and user space might
accidentially access unplugged memory.
So once the driver was loaded and detected the device along the
device-managed region, we just want to disallow any access via /dev/mem to
it.
In an ideal world, we would mark the whole region as busy ("owned by a
driver") and exclude it; however, that would be wrong, as we don't really
have actual system RAM at these ranges added to Linux ("busy system RAM").
Instead, we want to mark such ranges as "not actual busy system RAM but
still soft-reserved and prepared by a driver for future use."
Let's teach iomem_is_exclusive() to reject access to any range with
"IORESOURCE_SYSTEM_RAM | IORESOURCE_EXCLUSIVE", even if not busy and even
if "iomem=relaxed" is set. Introduce EXCLUSIVE_SYSTEM_RAM to make it
easier for applicable drivers to depend on this setting in their Kconfig.
For now, there are no applicable ranges and we'll modify virtio-mem next
to properly set IORESOURCE_EXCLUSIVE on the parent resource container it
creates to contain all actual busy system RAM added via
add_memory_driver_managed().
Link: https://lkml.kernel.org/r/20210920142856.17758-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
David Hildenbrand
|
b78dfa059f |
kernel/resource: clean up and optimize iomem_is_exclusive()
Patch series "virtio-mem: disallow mapping virtio-mem memory via /dev/mem", v5.
Let's add the basic infrastructure to exclude some physical memory regions
marked as "IORESOURCE_SYSTEM_RAM" completely from /dev/mem access, even
though they are not marked IORESOURCE_BUSY and even though "iomem=relaxed"
is set. Resource IORESOURCE_EXCLUSIVE for that purpose instead of adding
new flags to express something similar to "soft-busy" or "not busy yet,
but already prepared by a driver and not to be mapped by user space".
Use it for virtio-mem, to disallow mapping any virtio-mem memory via
/dev/mem to user space after the virtio-mem driver was loaded.
This patch (of 3):
We end up traversing subtrees of ranges we are not interested in; let's
optimize this case, skipping such subtrees, cleaning up the function a
bit.
For example, in the following configuration (/proc/iomem):
00000000-00000fff : Reserved
00001000-00057fff : System RAM
00058000-00058fff : Reserved
00059000-0009cfff : System RAM
0009d000-000fffff : Reserved
000a0000-000bffff : PCI Bus 0000:00
000c0000-000c3fff : PCI Bus 0000:00
000c4000-000c7fff : PCI Bus 0000:00
000c8000-000cbfff : PCI Bus 0000:00
000cc000-000cffff : PCI Bus 0000:00
000d0000-000d3fff : PCI Bus 0000:00
000d4000-000d7fff : PCI Bus 0000:00
000d8000-000dbfff : PCI Bus 0000:00
000dc000-000dffff : PCI Bus 0000:00
000e0000-000e3fff : PCI Bus 0000:00
000e4000-000e7fff : PCI Bus 0000:00
000e8000-000ebfff : PCI Bus 0000:00
000ec000-000effff : PCI Bus 0000:00
000f0000-000fffff : PCI Bus 0000:00
000f0000-000fffff : System ROM
00100000-3fffffff : System RAM
40000000-403fffff : Reserved
40000000-403fffff : pnp 00:00
40400000-80a79fff : System RAM
...
We don't have to look at any children of "0009d000-000fffff : Reserved"
if we can just skip these 15 items directly because the parent range is
not of interest.
Link: https://lkml.kernel.org/r/20210920142856.17758-1-david@redhat.com
Link: https://lkml.kernel.org/r/20210920142856.17758-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
Alistair Popple
|
eb1f065f90 |
kernel/resource: fix return code check in __request_free_mem_region
Splitting an earlier version of a patch that allowed calling __request_region() while holding the resource lock into a series of patches required changing the return code for the newly introduced __request_region_locked(). Unfortunately this change was not carried through to a subsequent commit |
||
|
Alistair Popple
|
56fd94919b |
kernel/resource: fix locking in request_free_mem_region
request_free_mem_region() is used to find an empty range of physical
addresses for hotplugging ZONE_DEVICE memory. It does this by iterating
over the range of possible addresses using region_intersects() to see if
the range is free before calling request_mem_region() to allocate the
region.
However the resource_lock is dropped between these two calls meaning by
the time request_mem_region() is called in request_free_mem_region()
another thread may have already reserved the requested region. This
results in unexpected failures and a message in the kernel log from
hitting this condition:
/*
* mm/hmm.c reserves physical addresses which then
* become unavailable to other users. Conflicts are
* not expected. Warn to aid debugging if encountered.
*/
if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) {
pr_warn("Unaddressable device %s %pR conflicts with %pR",
conflict->name, conflict, res);
These unexpected failures can be corrected by holding resource_lock across
the two calls. This also requires memory allocation to be performed prior
to taking the lock.
Link: https://lkml.kernel.org/r/20210419070109.4780-3-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Muchun Song <smuchun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
Alistair Popple
|
63cdafe0af |
kernel/resource: refactor __request_region to allow external locking
Refactor the portion of __request_region() done whilst holding the resource_lock into a separate function to allow callers to hold the lock. Link: https://lkml.kernel.org/r/20210419070109.4780-2-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Muchun Song <smuchun@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Alistair Popple
|
d486ccb252 |
kernel/resource: allow region_intersects users to hold resource_lock
Introduce a version of region_intersects() that can be called with the resource_lock already held. This will be used in a future fix to __request_free_mem_region(). [akpm@linux-foundation.org: make __region_intersects static] Link: https://lkml.kernel.org/r/20210419070109.4780-1-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Cc: David Hildenbrand <david@redhat.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Muchun Song <smuchun@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
David Hildenbrand
|
97523a4edb |
kernel/resource: remove first_lvl / siblings_only logic
All functions that search for IORESOURCE_SYSTEM_RAM or IORESOURCE_MEM resources now properly consider the whole resource tree, not just the first level. Let's drop the unused first_lvl / siblings_only logic. Remove documentation that indicates that some functions behave differently, all consider the full resource tree now. Link: https://lkml.kernel.org/r/20210325115326.7826-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Qian Cai <cai@lca.pw> Cc: Oscar Salvador <osalvador@suse.de> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
David Hildenbrand
|
3c9c797534 |
kernel/resource: make walk_mem_res() find all busy IORESOURCE_MEM resources
It used to be true that we can have system RAM (IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY) only on the first level in the resource tree. However, this is no longer holds for driver-managed system RAM (i.e., added via dax/kmem and virtio-mem), which gets added on lower levels, for example, inside device containers. IORESOURCE_SYSTEM_RAM is defined as IORESOURCE_MEM | IORESOURCE_SYSRAM and just a special type of IORESOURCE_MEM. The function walk_mem_res() only considers the first level and is used in arch/x86/mm/ioremap.c:__ioremap_check_mem() only. We currently fail to identify System RAM added by dax/kmem and virtio-mem as "IORES_MAP_SYSTEM_RAM", for example, allowing for remapping of such "normal RAM" in __ioremap_caller(). Let's find all IORESOURCE_MEM | IORESOURCE_BUSY resources, making the function behave similar to walk_system_ram_res(). Link: https://lkml.kernel.org/r/20210325115326.7826-3-david@redhat.com Fixes: |
||
|
David Hildenbrand
|
97f61c8f44 |
kernel/resource: make walk_system_ram_res() find all busy IORESOURCE_SYSTEM_RAM resources
Patch series "kernel/resource: make walk_system_ram_res() and walk_mem_res() search the whole tree", v2. Playing with kdump+virtio-mem I noticed that kexec_file_load() does not consider System RAM added via dax/kmem and virtio-mem when preparing the elf header for kdump. Looking into the details, the logic used in walk_system_ram_res() and walk_mem_res() seems to be outdated. walk_system_ram_range() already does the right thing, let's change walk_system_ram_res() and walk_mem_res(), and clean up. Loading a kdump kernel via "kexec -p -s" ... will result in the kdump kernel to also dump dax/kmem and virtio-mem added System RAM now. Note: kexec-tools on x86-64 also have to be updated to consider this memory in the kexec_load() case when processing /proc/iomem. This patch (of 3): It used to be true that we can have system RAM (IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY) only on the first level in the resource tree. However, this is no longer holds for driver-managed system RAM (i.e., added via dax/kmem and virtio-mem), which gets added on lower levels, for example, inside device containers. We have two users of walk_system_ram_res(), which currently only consideres the first level: a) kernel/kexec_file.c:kexec_walk_resources() -- We properly skip IORESOURCE_SYSRAM_DRIVER_MANAGED resources via locate_mem_hole_callback(), so even after this change, we won't be placing kexec images onto dax/kmem and virtio-mem added memory. No change. b) arch/x86/kernel/crash.c:fill_up_crash_elf_data() -- we're currently not adding relevant ranges to the crash elf header, resulting in them not getting dumped via kdump. This change fixes loading a crashkernel via kexec_file_load() and including dax/kmem and virtio-mem added System RAM in the crashdump on x86-64. Note that e.g,, arm64 relies on memblock data and, therefore, always considers all added System RAM already. Let's find all IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY resources, making the function behave like walk_system_ram_range(). Link: https://lkml.kernel.org/r/20210325115326.7826-1-david@redhat.com Link: https://lkml.kernel.org/r/20210325115326.7826-2-david@redhat.com Fixes: |
||
Daniel Vetter
|
71a1d8ed90 |
resource: Move devmem revoke code to resource framework
We want all iomem mmaps to consistently revoke ptes when the kernel takes over and CONFIG_IO_STRICT_DEVMEM is enabled. This includes the pci bar mmaps available through procfs and sysfs, which currently do not revoke mappings. To prepare for this, move the code from the /dev/kmem driver to kernel/resource.c. During review Jason spotted that barriers are used somewhat inconsistently. Fix that up while we shuffle this code, since it doesn't have an actual impact at runtime. Otherwise no semantic and behavioural changes intended, just code extraction and adjusting comments and names. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Hildenbrand <david@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-11-daniel.vetter@ffwll.ch |
||
Mauro Carvalho Chehab
|
3be8da5708 |
kernel/resource.c: fix kernel-doc markups
Kernel-doc markups should use this format:
identifier - description
While here, fix a kernel-doc tag that was using, instead,
a normal comment block.
[akpm@linux-foundation.org: coding style fixes]
Link: https://lkml.kernel.org/r/c5e38e1070f8dbe2f9607a10b44afe2875bd966c.1605521731.git.mchehab+huawei@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: "Jonathan Corbet" <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|
Andy Shevchenko
|
66f4fa32eb |
resource: Simplify region_intersects() by reducing conditionals
Now we have for 'other' and 'type' variables other type return 0 0 REGION_DISJOINT 0 x REGION_INTERSECTS x 0 REGION_DISJOINT x x REGION_MIXED Obviously it's easier to check 'type' for 0 first instead of currently checked 'other'. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Tested-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
||
|
David Hildenbrand
|
cb8e3c8b4f |
kernel/resource: make iomem_resource implicit in release_mem_region_adjustable()
"mem" in the name already indicates the root, similar to release_mem_region() and devm_request_mem_region(). Make it implicit. The only single caller always passes iomem_resource, other parents are not applicable. Suggested-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Link: https://lkml.kernel.org/r/20200916073041.10355-1-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
David Hildenbrand
|
9ca6551ee2 |
mm/memory_hotplug: MEMHP_MERGE_RESOURCE to specify merging of System RAM resources
Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where possible. Let's provide a flag (MEMHP_MERGE_RESOURCE) to specify that a resource either created within add_memory*() or passed via add_memory_resource() shall be marked mergeable and merged with applicable siblings. To implement that, we need a kernel/resource interface to mark selected System RAM resources mergeable (IORESOURCE_SYSRAM_MERGEABLE) and trigger merging. Note: We really want to merge after the whole operation succeeded, not directly when adding a resource to the resource tree (it would break add_memory_resource() and require splitting resources again when the operation failed - e.g., due to -ENOMEM). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Julien Grall <julien@xen.org> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Link: https://lkml.kernel.org/r/20200911103459.10306-6-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
David Hildenbrand
|
ec62d04e3f |
kernel/resource: make release_mem_region_adjustable() never fail
Patch series "selective merging of system ram resources", v4. Some add_memory*() users add memory in small, contiguous memory blocks. Examples include virtio-mem, hyper-v balloon, and the XEN balloon. This can quickly result in a lot of memory resources, whereby the actual resource boundaries are not of interest (e.g., it might be relevant for DIMMs, exposed via /proc/iomem to user space). We really want to merge added resources in this scenario where possible. Resources are effectively stored in a list-based tree. Having a lot of resources not only wastes memory, it also makes traversing that tree more expensive, and makes /proc/iomem explode in size (e.g., requiring kexec-tools to manually merge resources when creating a kdump header. The current kexec-tools resource count limit does not allow for more than ~100GB of memory with a memory block size of 128MB on x86-64). Let's allow to selectively merge system ram resources by specifying a new flag for add_memory*(). Patch #5 contains a /proc/iomem example. Only tested with virtio-mem. This patch (of 8): Let's make sure splitting a resource on memory hotunplug will never fail. This will become more relevant once we merge selected System RAM resources - then, we'll trigger that case more often on memory hotunplug. In general, this function is already unlikely to fail. When we remove memory, we free up quite a lot of metadata (memmap, page tables, memory block device, etc.). The only reason it could really fail would be when injecting allocation errors. All other error cases inside release_mem_region_adjustable() seem to be sanity checks if the function would be abused in different context - let's add WARN_ON_ONCE() in these cases so we can catch them. [natechancellor@gmail.com: fix use of ternary condition in release_mem_region_adjustable] Link: https://lkml.kernel.org/r/20200922060748.2452056-1-natechancellor@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/1159 Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Grall <julien@xen.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Roger Pau Monn <roger.pau@citrix.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Liu <wei.liu@kernel.org> Link: https://lkml.kernel.org/r/20200911103459.10306-2-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Dan Williams
|
73fb952d83 |
resource: report parent to walk_iomem_res_desc() callback
In support of detecting whether a resource might have been been claimed, report the parent to the walk_iomem_res_desc() callback. For example, the ACPI HMAT parser publishes "hmem" platform devices per target range. However, if the HMAT is disabled / missing a fallback driver can attach devices to the raw memory ranges as a fallback if it sees unclaimed / orphan "Soft Reserved" resources in the resource tree. Otherwise, find_next_iomem_res() returns a resource with garbage data from the stack allocation in __walk_iomem_res_desc() for the res->parent field. There are currently no users that expect ->child and ->sibling to be valid, and the resource_lock would be needed to traverse them. Use a compound literal to implicitly zero initialize the fields that are not being returned in addition to setting ->parent. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brice Goglin <Brice.Goglin@inria.fr> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Dave Jiang <dave.jiang@intel.com> Cc: David Airlie <airlied@linux.ie> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Jia He <justin.he@arm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Hulk Robot <hulkci@huawei.com> Cc: Jason Yan <yanaijie@huawei.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: kernel test robot <lkp@intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Link: https://lkml.kernel.org/r/159643097166.4062302.11875688887228572793.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Dan Williams
|
3234ac664a |
/dev/mem: Revoke mappings when a driver claims the region
Close the hole of holding a mapping over kernel driver takeover event of a given address range. Commit |
||
|
David Hildenbrand
|
00ff9a91bd |
mm/memory_hotplug.c: use PFN_UP / PFN_DOWN in walk_system_ram_range()
Patch series "mm/memory_hotplug: online_pages() cleanups", v2. Some cleanups (+ one fix for a special case) in the context of online_pages(). This patch (of 5): This makes it clearer that we will never call func() with duplicate PFNs in case we have multiple sub-page memory resources. All unaligned parts of PFNs are completely discarded. Link: http://lkml.kernel.org/r/20190814154109.3448-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Wei Yang <richardw.yang@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Nadav Amit <namit@vmware.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Arun KS <arunks@codeaurora.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Christoph Hellwig
|
0c38519039 |
resource: add a not device managed request_free_mem_region variant
Factor out the guts of devm_request_free_mem_region so that we can implement both a device managed and a manually release version as tiny wrappers around it. Link: https://lore.kernel.org/r/20190818090557.17853-2-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Bharata B Rao <bharata@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> |
||
Nadav Amit
|
756398750e |
resource: avoid unnecessary lookups in find_next_iomem_res()
find_next_iomem_res() shows up to be a source for overhead in dax benchmarks. Improve performance by not considering children of the tree if the top level does not match. Since the range of the parents should include the range of the children such check is redundant. Running sysbench on dax (pmem emulation, with write_cache disabled): sysbench fileio --file-total-size=3G --file-test-mode=rndwr \ --file-io-mode=mmap --threads=4 --file-fsync-mode=fdatasync run Provides the following results: events (avg/stddev) ------------------- 5.2-rc3: 1247669.0000/16075.39 w/patch: 1286320.5000/16402.72 (+3%) Link: http://lkml.kernel.org/r/20190613045903.4922-3-namit@vmware.com Signed-off-by: Nadav Amit <namit@vmware.com> Cc: Borislav Petkov <bp@suse.de> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Nadav Amit
|
49f17c26c1 |
resource: fix locking in find_next_iomem_res()
Since resources can be removed, locking should ensure that the resource
is not removed while accessing it. However, find_next_iomem_res() does
not hold the lock while copying the data of the resource.
Keep holding the lock while the data is copied. While at it, change the
return value to a more informative value. It is disregarded by the
callers.
[akpm@linux-foundation.org: fix find_next_iomem_res() documentation]
Link: http://lkml.kernel.org/r/20190613045903.4922-2-namit@vmware.com
Fixes:
|
||
|
Christoph Hellwig
|
0092908d16 |
mm: factor out a devm_request_free_mem_region helper
Keep the physical address allocation that hmm_add_device does with the rest of the resource code, and allow future reuse of it without the hmm wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> |
||
Thomas Gleixner
|
457c899653 |
treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
||
Wei Yang
|
f6c6010a07 |
mm/resource: Use resource_overlaps() to simplify region_intersects()
The three checks in region_intersects() are basically an open-coded version of resource_overlaps() - so use the real thing. Also fix typos in comments while at it. Signed-off-by: Wei Yang <richardw.yang@linux.intel.com> Reviewed-by: Like Xu <like.xu@linux.intel.com> Reviewed-by: Yuan Yao <yuan.yao@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: bhelgaas@google.com Cc: bp@suse.de Cc: dan.j.williams@intel.com Cc: jack@suse.cz Cc: rdunlap@infradead.org Cc: tiwai@suse.de Link: http://lkml.kernel.org/r/20190305083432.23675-1-richardw.yang@linux.intel.com [ Rewrote the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|
Linus Torvalds
|
f67e3fb489 |
device-dax for 5.1
* Replace the /sys/class/dax device model with /sys/bus/dax, and include
a compat driver so distributions can opt-in to the new ABI.
* Allow for an alternative driver for the device-dax address-range
* Introduce the 'kmem' driver to hotplug / assign a device-dax
address-range to the core-mm.
* Arrange for the device-dax target-node to be onlined so that the newly
added memory range can be uniquely referenced by numa apis.
-----BEGIN PGP SIGNATURE-----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=hfa3
-----END PGP SIGNATURE-----
Merge tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull device-dax updates from Dan Williams:
"New device-dax infrastructure to allow persistent memory and other
"reserved" / performance differentiated memories, to be assigned to
the core-mm as "System RAM".
Some users want to use persistent memory as additional volatile
memory. They are willing to cope with potential performance
differences, for example between DRAM and 3D Xpoint, and want to use
typical Linux memory management apis rather than a userspace memory
allocator layered over an mmap() of a dax file. The administration
model is to decide how much Persistent Memory (pmem) to use as System
RAM, create a device-dax-mode namespace of that size, and then assign
it to the core-mm. The rationale for device-dax is that it is a
generic memory-mapping driver that can be layered over any "special
purpose" memory, not just pmem. On subsequent boots udev rules can be
used to restore the memory assignment.
One implication of using pmem as RAM is that mlock() no longer keeps
data off persistent media. For this reason it is recommended to enable
NVDIMM Security (previously merged for 5.0) to encrypt pmem contents
at rest. We considered making this recommendation an actively enforced
requirement, but in the end decided to leave it as a distribution /
administrator policy to allow for emulation and test environments that
lack security capable NVDIMMs.
Summary:
- Replace the /sys/class/dax device model with /sys/bus/dax, and
include a compat driver so distributions can opt-in to the new ABI.
- Allow for an alternative driver for the device-dax address-range
- Introduce the 'kmem' driver to hotplug / assign a device-dax
address-range to the core-mm.
- Arrange for the device-dax target-node to be onlined so that the
newly added memory range can be uniquely referenced by numa apis"
NOTE! I'm not entirely happy with the whole "PMEM as RAM" model because
we currently have special - and very annoying rules in the kernel about
accessing PMEM only with the "MC safe" accessors, because machine checks
inside the regular repeat string copy functions can be fatal in some
(not described) circumstances.
And apparently the PMEM modules can cause that a lot more than regular
RAM. The argument is that this happens because PMEM doesn't necessarily
get scrubbed at boot like RAM does, but that is planned to be added for
the user space tooling.
Quoting Dan from another email:
"The exposure can be reduced in the volatile-RAM case by scanning for
and clearing errors before it is onlined as RAM. The userspace tooling
for that can be in place before v5.1-final. There's also runtime
notifications of errors via acpi_nfit_uc_error_notify() from
background scrubbers on the DIMM devices. With that mechanism the
kernel could proactively clear newly discovered poison in the volatile
case, but that would be additional development more suitable for v5.2.
I understand the concern, and the need to highlight this issue by
tapping the brakes on feature development, but I don't see PMEM as RAM
making the situation worse when the exposure is also there via DAX in
the PMEM case. Volatile-RAM is arguably a safer use case since it's
possible to repair pages where the persistent case needs active
application coordination"
* tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
device-dax: "Hotplug" persistent memory for use like normal RAM
mm/resource: Let walk_system_ram_range() search child resources
mm/memory-hotplug: Allow memory resources to be children
mm/resource: Move HMM pr_debug() deeper into resource code
mm/resource: Return real error codes from walk failures
device-dax: Add a 'modalias' attribute to DAX 'bus' devices
device-dax: Add a 'target_node' attribute
device-dax: Auto-bind device after successful new_id
acpi/nfit, device-dax: Identify differentiated memory with a unique numa-node
device-dax: Add /sys/class/dax backwards compatibility
device-dax: Add support for a dax override driver
device-dax: Move resource pinning+mapping into the common driver
device-dax: Introduce bus + driver model
device-dax: Start defining a dax bus model
device-dax: Remove multi-resource infrastructure
device-dax: Kill dax_region base
device-dax: Kill dax_region ida
|
||
Dave Hansen
|
2b539aefe9 |
mm/resource: Let walk_system_ram_range() search child resources
In the process of onlining memory, we use walk_system_ram_range() to find the actual RAM areas inside of the area being onlined. However, it currently only finds memory resources which are "top-level" iomem_resources. Children are not currently searched which causes it to skip System RAM in areas like this (in the format of /proc/iomem): a0000000-bfffffff : Persistent Memory (legacy) a0000000-afffffff : System RAM Changing the true->false here allows children to be searched as well. We need this because we add a new "System RAM" resource underneath the "persistent memory" resource when we use persistent memory in a volatile mode. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ross Zwisler <zwisler@kernel.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: linux-nvdimm@lists.01.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: Huang Ying <ying.huang@intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
||
|
Dave Hansen
|
b926b7f3ba |
mm/resource: Move HMM pr_debug() deeper into resource code
HMM consumes physical address space for its own use, even though nothing is mapped or accessible there. It uses a special resource description (IORES_DESC_DEVICE_PRIVATE_MEMORY) to uniquely identify these areas. When HMM consumes address space, it makes a best guess about what to consume. However, it is possible that a future memory or device hotplug can collide with the reserved area. In the case of these conflicts, there is an error message in register_memory_resource(). Later patches in this series move register_memory_resource() from using request_resource_conflict() to __request_region(). Unfortunately, __request_region() does not return the conflict like the previous function did, which makes it impossible to check for IORES_DESC_DEVICE_PRIVATE_MEMORY in a conflicting resource. Instead of warning in register_memory_resource(), move the check into the core resource code itself (__request_region()) where the conflicting resource _is_ available. This has the added bonus of producing a warning in case of HMM conflicts with devices *or* RAM address space, as opposed to the RAM- only warnings that were there previously. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Jerome Glisse <jglisse@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ross Zwisler <zwisler@kernel.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: linux-nvdimm@lists.01.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: Huang Ying <ying.huang@intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Keith Busch <keith.busch@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> |
||
|
Dave Hansen
|
5cd401ace9 |
mm/resource: Return real error codes from walk failures
walk_system_ram_range() can return an error code either becuase
*it* failed, or because the 'func' that it calls returned an
error. The memory hotplug does the following:
ret = walk_system_ram_range(..., func);
if (ret)
return ret;
and 'ret' makes it out to userspace, eventually. The problem
s, walk_system_ram_range() failues that result from *it* failing
(as opposed to 'func') return -1. That leads to a very odd
-EPERM (-1) return code out to userspace.
Make walk_system_ram_range() return -EINVAL for internal
failures to keep userspace less confused.
This return code is compatible with all the callers that I
audited.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: linux-nvdimm@lists.01.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: Huang Ying <ying.huang@intel.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Keith Busch <keith.busch@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
|
||
Christophe Leroy
|
26b523356f |
powerpc: Drop page_is_ram() and walk_system_ram_range()
Since commit |
||
Oscar Salvador
|
65c7878413 |
kernel, resource: check for IORESOURCE_SYSRAM in release_mem_region_adjustable
This is a preparation for the next patch. Currently, we only call release_mem_region_adjustable() in __remove_pages if the zone is not ZONE_DEVICE, because resources that belong to HMM/devm are being released by themselves with devm_release_mem_region. Since we do not want to touch any zone/page stuff during the removing of the memory (but during the offlining), we do not want to check for the zone here. So we need another way to tell release_mem_region_adjustable() to not realease the resource in case it belongs to HMM/devm. HMM/devm acquires/releases a resource through devm_request_mem_region/devm_release_mem_region. These resources have the flag IORESOURCE_MEM, while resources acquired by hot-add memory path (register_memory_resource()) contain IORESOURCE_SYSTEM_RAM. So, we can check for this flag in release_mem_region_adjustable, and if the resource does not contain such flag, we know that we are dealing with a HMM/devm resource, so we can back off. Link: http://lkml.kernel.org/r/20181127162005.15833-3-osalvador@suse.de Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
Borislav Petkov
|
f26621e60b |
resource/docs: Complete kernel-doc style function documentation
Add the missing kernel-doc style function parameters documentation.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: linux-tip-commits@vger.kernel.org
Cc: rdunlap@infradead.org
Fixes:
|
||
Randy Dunlap
|
f75d651587 |
resource/docs: Fix new kernel-doc warnings
The first group of warnings is caused by a "/**" kernel-doc notation
marker but the function comments are not in kernel-doc format.
Also add another error return value here.
../kernel/resource.c:337: warning: Function parameter or member 'start' not described in 'find_next_iomem_res'
../kernel/resource.c:337: warning: Function parameter or member 'end' not described in 'find_next_iomem_res'
../kernel/resource.c:337: warning: Function parameter or member 'flags' not described in 'find_next_iomem_res'
../kernel/resource.c:337: warning: Function parameter or member 'desc' not described in 'find_next_iomem_res'
../kernel/resource.c:337: warning: Function parameter or member 'first_lvl' not described in 'find_next_iomem_res'
../kernel/resource.c:337: warning: Function parameter or member 'res' not described in 'find_next_iomem_res'
Add the missing function parameter documentation for the other warnings:
../kernel/resource.c:409: warning: Function parameter or member 'arg' not described in 'walk_iomem_res_desc'
../kernel/resource.c:409: warning: Function parameter or member 'func' not described in 'walk_iomem_res_desc'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes:
|
||
|
Borislav Petkov
|
b69c2e20f6 |
resource: Clean it up a bit
- Drop BUG_ON()s and do normal error handling instead, in find_next_iomem_res(). - Align function arguments on opening braces. - Get rid of local var sibling_only in find_next_iomem_res(). - Shorten unnecessarily long first_level_children_only arg name. Signed-off-by: Borislav Petkov <bp@suse.de> CC: Andrew Morton <akpm@linux-foundation.org> CC: Bjorn Helgaas <bhelgaas@google.com> CC: Brijesh Singh <brijesh.singh@amd.com> CC: Dan Williams <dan.j.williams@intel.com> CC: H. Peter Anvin <hpa@zytor.com> CC: Lianbo Jiang <lijiang@redhat.com> CC: Takashi Iwai <tiwai@suse.de> CC: Thomas Gleixner <tglx@linutronix.de> CC: Tom Lendacky <thomas.lendacky@amd.com> CC: Vivek Goyal <vgoyal@redhat.com> CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com> CC: bhe@redhat.com CC: dan.j.williams@intel.com CC: dyoung@redhat.com CC: kexec@lists.infradead.org CC: mingo@redhat.com Link: <new submission> |
||
Bjorn Helgaas
|
010a93bf97 |
resource: Fix find_next_iomem_res() iteration issue
Previously find_next_iomem_res() used "*res" as both an input parameter for the range to search and the type of resource to search for, and an output parameter for the resource we found, which makes the interface confusing. The current callers use find_next_iomem_res() incorrectly because they allocate a single struct resource and use it for repeated calls to find_next_iomem_res(). When find_next_iomem_res() returns a resource, it overwrites the start, end, flags, and desc members of the struct. If we call find_next_iomem_res() again, we must update or restore these fields. The previous code restored res.start and res.end, but not res.flags or res.desc. Since the callers did not restore res.flags, if they searched for flags IORESOURCE_MEM | IORESOURCE_BUSY and found a resource with flags IORESOURCE_MEM | IORESOURCE_BUSY | IORESOURCE_SYSRAM, the next search would incorrectly skip resources unless they were also marked as IORESOURCE_SYSRAM. Fix this by restructuring the interface so it takes explicit "start, end, flags" parameters and uses "*res" only as an output parameter. Based on a patch by Lianbo Jiang <lijiang@redhat.com>. [ bp: While at it: - make comments kernel-doc style. - Originally-by: http://lore.kernel.org/lkml/20180921073211.20097-2-lijiang@redhat.com Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> CC: Andrew Morton <akpm@linux-foundation.org> CC: Brijesh Singh <brijesh.singh@amd.com> CC: Dan Williams <dan.j.williams@intel.com> CC: H. Peter Anvin <hpa@zytor.com> CC: Lianbo Jiang <lijiang@redhat.com> CC: Takashi Iwai <tiwai@suse.de> CC: Thomas Gleixner <tglx@linutronix.de> CC: Tom Lendacky <thomas.lendacky@amd.com> CC: Vivek Goyal <vgoyal@redhat.com> CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com> CC: bhe@redhat.com CC: dan.j.williams@intel.com CC: dyoung@redhat.com CC: kexec@lists.infradead.org CC: mingo@redhat.com CC: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/153805812916.1157.177580438135143788.stgit@bhelgaas-glaptop.roam.corp.google.com |
||
|
Bjorn Helgaas
|
a98959fdbd |
resource: Include resource end in walk_*() interfaces
find_next_iomem_res() finds an iomem resource that covers part of a range
described by "start, end". All callers expect that range to be inclusive,
i.e., both start and end are included, but find_next_iomem_res() doesn't
handle the end address correctly.
If it finds an iomem resource that contains exactly the end address, it
skips it, e.g., if "start, end" is [0x0-0x10000] and there happens to be an
iomem resource [mem 0x10000-0x10000] (the single byte at 0x10000), we skip
it:
find_next_iomem_res(...)
{
start = 0x0;
end = 0x10000;
for (p = next_resource(...)) {
# p->start = 0x10000;
# p->end = 0x10000;
# we *should* return this resource, but this condition is false:
if ((p->end >= start) && (p->start < end))
break;
Adjust find_next_iomem_res() so it allows a resource that includes the
single byte at the end of the range. This is a corner case that we
probably don't see in practice.
Fixes:
|
||
|
Linus Torvalds
|
7d3bf613e9 |
libnvdimm for 4.18
* DAX broke a fundamental assumption of truncate of file mapped pages.
The truncate path assumed that it is safe to disconnect a pinned page
from a file and let the filesystem reclaim the physical block. With DAX
the page is equivalent to the filesystem block. Introduce
dax_layout_busy_page() to enable filesystems to wait for pinned DAX
pages to be released. Without this wait a filesystem could allocate
blocks under active device-DMA to a new file.
* DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
* Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they are not
necessary. The table indicates whether CPU caches are power-fail
protected. Clarify that a deep flush is always performed on
REQ_{FUA,PREFLUSH} requests.
-----BEGIN PGP SIGNATURE-----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=4bfw
-----END PGP SIGNATURE-----
Merge tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"This adds a user for the new 'bytes-remaining' updates to
memcpy_mcsafe() that you already received through Ingo via the
x86-dax- for-linus pull.
Not included here, but still targeting this cycle, is support for
handling memory media errors (poison) consumed via userspace dax
mappings.
Summary:
- DAX broke a fundamental assumption of truncate of file mapped
pages. The truncate path assumed that it is safe to disconnect a
pinned page from a file and let the filesystem reclaim the physical
block. With DAX the page is equivalent to the filesystem block.
Introduce dax_layout_busy_page() to enable filesystems to wait for
pinned DAX pages to be released. Without this wait a filesystem
could allocate blocks under active device-DMA to a new file.
- DAX arranges for the block layer to be bypassed and uses
dax_direct_access() + copy_to_iter() to satisfy read(2) calls.
However, the memcpy_mcsafe() facility is available through the pmem
block driver. In order to safely handle media errors, via the DAX
block-layer bypass, introduce copy_to_iter_mcsafe().
- Fix cache management policy relative to the ACPI NFIT Platform
Capabilities Structure to properly elide cache flushes when they
are not necessary. The table indicates whether CPU caches are
power-fail protected. Clarify that a deep flush is always performed
on REQ_{FUA,PREFLUSH} requests"
* tag 'libnvdimm-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (21 commits)
dax: Use dax_write_cache* helpers
libnvdimm, pmem: Do not flush power-fail protected CPU caches
libnvdimm, pmem: Unconditionally deep flush on *sync
libnvdimm, pmem: Complete REQ_FLUSH => REQ_PREFLUSH
acpi, nfit: Remove ecc_unit_size
dax: dax_insert_mapping_entry always succeeds
libnvdimm, e820: Register all pmem resources
libnvdimm: Debug probe times
linvdimm, pmem: Preserve read-only setting for pmem devices
x86, nfit_test: Add unit test for memcpy_mcsafe()
pmem: Switch to copy_to_iter_mcsafe()
dax: Report bytes remaining in dax_iomap_actor()
dax: Introduce a ->copy_to_iter dax operation
uio, lib: Fix CONFIG_ARCH_HAS_UACCESS_MCSAFE compilation
xfs, dax: introduce xfs_break_dax_layouts()
xfs: prepare xfs_break_layouts() for another layout type
xfs: prepare xfs_break_layouts() to be called with XFS_MMAPLOCK_EXCL
mm, fs, dax: handle layout changes to pinned dax mappings
mm: fix __gup_device_huge vs unmap
mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS
...
|
||
|
Dan Williams
|
d76401ade0 |
libnvdimm, e820: Register all pmem resources
There is currently a mismatch between the resources that will trigger
the e820_pmem driver to register/load and the resources that will
actually be surfaced as pmem ranges. register_e820_pmem() uses
walk_iomem_res_desc() which includes children and siblings. In contrast,
e820_pmem_probe() only considers top level resources. For example the
following resource tree results in the driver being loaded, but no
resources being registered:
398000000000-39bfffffffff : PCI Bus 0000:ae
39be00000000-39bf07ffffff : PCI Bus 0000:af
39be00000000-39beffffffff : 0000:af:00.0
39be10000000-39beffffffff : Persistent Memory (legacy)
Fix this up to allow definitions of "legacy" pmem ranges anywhere in
system-physical address space. Not that it is a recommended or safe to
define a pmem range in PCI space, but it is useful for debug /
experimentation, and the restriction on being a top-level resource was
arbitrary.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
|
||
|
Christoph Hellwig
|
4e292a9667 |
resource: switch to proc_create_seq_data
And use the root resource directly from the proc private data. Signed-off-by: Christoph Hellwig <hch@lst.de> |
||
Takashi Iwai
|
60bb83b811 |
resource: fix integer overflow at reallocation
We've got a bug report indicating a kernel panic at booting on an x86-32 system, and it turned out to be the invalid PCI resource assigned after reallocation. __find_resource() first aligns the resource start address and resets the end address with start+size-1 accordingly, then checks whether it's contained. Here the end address may overflow the integer, although resource_contains() still returns true because the function validates only start and end address. So this ends up with returning an invalid resource (start > end). There was already an attempt to cover such a problem in the commit |
||
|
Linus Torvalds
|
a2e5790d84 |
Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton: - kasan updates - procfs - lib/bitmap updates - other lib/ updates - checkpatch tweaks - rapidio - ubsan - pipe fixes and cleanups - lots of other misc bits * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits) Documentation/sysctl/user.txt: fix typo MAINTAINERS: update ARM/QUALCOMM SUPPORT patterns MAINTAINERS: update various PALM patterns MAINTAINERS: update "ARM/OXNAS platform support" patterns MAINTAINERS: update Cortina/Gemini patterns MAINTAINERS: remove ARM/CLKDEV SUPPORT file pattern MAINTAINERS: remove ANDROID ION pattern mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors mm: docs: fix parameter names mismatch mm: docs: fixup punctuation pipe: read buffer limits atomically pipe: simplify round_pipe_size() pipe: reject F_SETPIPE_SZ with size over UINT_MAX pipe: fix off-by-one error when checking buffer limits pipe: actually allow root to exceed the pipe buffer limits pipe, sysctl: remove pipe_proc_fn() pipe, sysctl: drop 'min' parameter from pipe-max-size converter kasan: rework Kconfig settings crash_dump: is_kdump_kernel can be boolean kernel/mutex: mutex_is_locked can be boolean ... |
||
Yaowei Bai
|
9825b451f9 |
kernel/resource: iomem_is_exclusive can be boolean
Make iomem_is_exclusive return bool due to this particular function only using either one or zero as its return value. No functional change. Link: http://lkml.kernel.org/r/1513266622-15860-5-git-send-email-baiyaowei@cmss.chinamobile.com Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
|
Bjorn Helgaas
|
f37e2334bc |
resource: Set type when reserving new regions
Set resource structs inserted by __reserve_region_with_split() to have the correct type. Setting the type doesn't fix any functional problem but makes %pR on the resource work better. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> |