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authorLinus Torvalds <torvalds@linux-foundation.org>2016-01-13 19:15:14 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-13 19:15:14 -0800
commitd080827f850ba4df5b955d5ca8c8c0fc92fe18c0 (patch)
tree37262315200bbbe50bdd64ce3011951a92855159 /lib
parentcbd88cd4c07f9361914ab7fd7e21c9227986fe68 (diff)
parent8b63b6bfc1a551acf154061699028c7032d7890c (diff)
downloadlinux-d080827f850ba4df5b955d5ca8c8c0fc92fe18c0.tar.bz2
Merge tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams: "The bulk of this has appeared in -next and independently received a build success notification from the kbuild robot. The 'for-4.5/block- dax' topic branch was rebased over the weekend to drop the "block device end-of-life" rework that Al would like to see re-implemented with a notifier, and to address bug reports against the badblocks integration. There is pending feedback against "libnvdimm: Add a poison list and export badblocks" received last week. Linda identified some localized fixups that we will handle incrementally. Summary: - Media error handling: The 'badblocks' implementation that originated in md-raid is up-levelled to a generic capability of a block device. This initial implementation is limited to being consulted in the pmem block-i/o path. Later, 'badblocks' will be consulted when creating dax mappings. - Raw block device dax: For virtualization and other cases that want large contiguous mappings of persistent memory, add the capability to dax-mmap a block device directly. - Increased /dev/mem restrictions: Add an option to treat all io-memory as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access while a driver is actively using an address range. This behavior is controlled via the new CONFIG_IO_STRICT_DEVMEM option and can be overridden by the existing "iomem=relaxed" kernel command line option. - Miscellaneous fixes include a 'pfn'-device huge page alignment fix, block device shutdown crash fix, and other small libnvdimm fixes" * tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (32 commits) block: kill disk_{check|set|clear|alloc}_badblocks libnvdimm, pmem: nvdimm_read_bytes() badblocks support pmem, dax: disable dax in the presence of bad blocks pmem: fail io-requests to known bad blocks libnvdimm: convert to statically allocated badblocks libnvdimm: don't fail init for full badblocks list block, badblocks: introduce devm_init_badblocks block: clarify badblocks lifetime badblocks: rename badblocks_free to badblocks_exit libnvdimm, pmem: move definition of nvdimm_namespace_add_poison to nd.h libnvdimm: Add a poison list and export badblocks nfit_test: Enable DSMs for all test NFITs md: convert to use the generic badblocks code block: Add badblock management for gendisks badblocks: Add core badblock management code block: fix del_gendisk() vs blkdev_ioctl crash block: enable dax for raw block devices block: introduce bdev_file_inode() restrict /dev/mem to idle io memory ranges arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug ...
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig.debug39
1 files changed, 39 insertions, 0 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e2a236a7341f..ee1ac1cc082c 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1886,3 +1886,42 @@ source "samples/Kconfig"
source "lib/Kconfig.kgdb"
+config ARCH_HAS_DEVMEM_IS_ALLOWED
+ bool
+
+config STRICT_DEVMEM
+ bool "Filter access to /dev/mem"
+ depends on MMU
+ depends on ARCH_HAS_DEVMEM_IS_ALLOWED
+ default y if TILE || PPC
+ ---help---
+ If this option is disabled, you allow userspace (root) access to all
+ of memory, including kernel and userspace memory. Accidental
+ access to this is obviously disastrous, but specific access can
+ be used by people debugging the kernel. Note that with PAT support
+ enabled, even in this case there are restrictions on /dev/mem
+ use due to the cache aliasing requirements.
+
+ If this option is switched on, and IO_STRICT_DEVMEM=n, the /dev/mem
+ file only allows userspace access to PCI space and the BIOS code and
+ data regions. This is sufficient for dosemu and X and all common
+ users of /dev/mem.
+
+ If in doubt, say Y.
+
+config IO_STRICT_DEVMEM
+ bool "Filter I/O access to /dev/mem"
+ depends on STRICT_DEVMEM
+ default STRICT_DEVMEM
+ ---help---
+ If this option is disabled, you allow userspace (root) access to all
+ io-memory regardless of whether a driver is actively using that
+ range. Accidental access to this is obviously disastrous, but
+ specific access can be used by people debugging kernel drivers.
+
+ If this option is switched on, the /dev/mem file only allows
+ userspace access to *idle* io-memory ranges (see /proc/iomem) This
+ may break traditional users of /dev/mem (dosemu, legacy X, etc...)
+ if the driver using a given range cannot be disabled.
+
+ If in doubt, say Y.