kernel/linux.git/drivers/of, branch linux-4.20.y

of: overlay: do not duplicate properties from overlay for new nodes

2019-02-06T16:27:45+00:00

commit 8814dc46bd9e347d4de55ec5bf8f16ea54470499 upstream. When allocating a new node, add_changeset_node() was duplicating the properties from the respective node in the overlay instead of allocating a node with no properties. When this patch is applied the errors reported by the devictree unittest from patch "of: overlay: add tests to validate kfrees from overlay removal" will no longer occur. These error messages are of the form: "OF: ERROR: ..." and the unittest results will change from: ### dt-test ### end of unittest - 203 passed, 7 failed to ### dt-test ### end of unittest - 210 passed, 0 failed Tested-by: Alan Tull Signed-off-by: Frank Rowand Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

of: overlay: use prop add changeset entry for property in new nodes

2019-02-06T16:27:44+00:00

commit 6b4955ba7bc05e40c8c41071cc121bc26ca65277 upstream. The changeset entry 'update property' was used for new properties in an overlay instead of 'add property'. The decision of whether to use 'update property' was based on whether the property already exists in the subtree where the node is being spliced into. At the top level of creating a changeset describing the overlay, the target node is in the live devicetree, so checking whether the property exists in the target node returns the correct result. As soon as the changeset creation algorithm recurses into a new node, the target is no longer in the live devicetree, but is instead in the detached overlay tree, thus all properties are incorrectly found to already exist in the target. This fix will expose another devicetree bug that will be fixed in the following patch in the series. When this patch is applied the errors reported by the devictree unittest will change, and the unittest results will change from: ### dt-test ### end of unittest - 210 passed, 0 failed to ### dt-test ### end of unittest - 203 passed, 7 failed Tested-by: Alan Tull Signed-off-by: Frank Rowand Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

of: overlay: add missing of_node_get() in __of_attach_node_sysfs

2019-02-06T16:27:44+00:00

commit 5b2c2f5a0ea3a43e0dee78059e34c7cb54136dcc upstream. There is a matching of_node_put() in __of_detach_node_sysfs() Remove misleading comment from function header comment for of_detach_node(). This patch may result in memory leaks from code that directly calls the dynamic node add and delete functions directly instead of using changesets. This commit should result in powerpc systems that dynamically allocate a node, then later deallocate the node to have a memory leak when the node is deallocated. The next commit will fix the leak. Tested-by: Alan Tull Acked-by: Michael Ellerman (powerpc) Signed-off-by: Frank Rowand Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

of: overlay: add tests to validate kfrees from overlay removal

2019-02-06T16:27:44+00:00

commit 144552c786925314c1e7cb8f91a71dae1aca8798 upstream. Add checks: - attempted kfree due to refcount reaching zero before overlay is removed - properties linked to an overlay node when the node is removed - node refcount > one during node removal in a changeset destroy, if the node was created by the changeset After applying this patch, several validation warnings will be reported from the devicetree unittest during boot due to pre-existing devicetree bugs. The warnings will be similar to: OF: ERROR: of_node_release(), unexpected properties in /testcase-data/overlay-node/test-bus/test-unittest11 OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /testcase-data-2/substation@100/ hvac-medium-2 Tested-by: Alan Tull Signed-off-by: Frank Rowand Cc: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

of: overlay: add missing of_node_put() after add new node to changeset

2019-01-26T08:20:40+00:00

[ Upstream commit 7c528e457d53c75107d5aa56892316d265c778de ] The refcount of a newly added overlay node decrements to one (instead of zero) when the overlay changeset is destroyed. This change will cause the final decrement be to zero. After applying this patch, new validation warnings will be reported from the devicetree unittest during boot due to a pre-existing devicetree bug. The warnings will be similar to: OF: ERROR: memory leak before free overlay changeset, /testcase-data/overlay-node/test-bus/test-unittest4 This pre-existing devicetree bug will also trigger a WARN_ONCE() from refcount_sub_and_test_checked() when an overlay changeset is destroyed without having first been applied. This scenario occurs when an error in the overlay is detected during the overlay changeset creation: WARNING: CPU: 0 PID: 1 at lib/refcount.c:187 refcount_sub_and_test_checked+0xa8/0xbc refcount_t: underflow; use-after-free. (unwind_backtrace) from (show_stack+0x10/0x14) (show_stack) from (dump_stack+0x6c/0x8c) (dump_stack) from (__warn+0xdc/0x104) (__warn) from (warn_slowpath_fmt+0x44/0x6c) (warn_slowpath_fmt) from (refcount_sub_and_test_checked+0xa8/0xbc) (refcount_sub_and_test_checked) from (kobject_put+0x24/0x208) (kobject_put) from (of_changeset_destroy+0x2c/0xb4) (of_changeset_destroy) from (free_overlay_changeset+0x1c/0x9c) (free_overlay_changeset) from (of_overlay_remove+0x284/0x2cc) (of_overlay_remove) from (of_unittest_apply_revert_overlay_check.constprop.4+0xf8/0x1e8) (of_unittest_apply_revert_overlay_check.constprop.4) from (of_unittest_overlay+0x960/0xed8) (of_unittest_overlay) from (of_unittest+0x1cc4/0x2138) (of_unittest) from (do_one_initcall+0x4c/0x28c) (do_one_initcall) from (kernel_init_freeable+0x29c/0x378) (kernel_init_freeable) from (kernel_init+0x8/0x110) (kernel_init) from (ret_from_fork+0x14/0x2c) Tested-by: Alan Tull Signed-off-by: Frank Rowand Signed-off-by: Sasha Levin

OF: properties: add missing of_node_put

2019-01-22T20:09:53+00:00

commit 28b170e88bc0c7509e6724717c15cb4b5686026e upstream. Add an of_node_put when the result of of_graph_get_remote_port_parent is not available. The semantic match that finds this problem is as follows (http://coccinelle.lip6.fr): // @r exists@ local idexpression e; expression x; @@ e = of_graph_get_remote_port_parent(...); ... when != x = e when != true e == NULL when != of_node_put(e) when != of_fwnode_handle(e) ( return e; | *return ...; ) // Signed-off-by: Julia Lawall Cc: stable@vger.kernel.org Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

of: __of_detach_node() - remove node from phandle cache

2019-01-13T08:24:09+00:00

commit 5801169a2ed20003f771acecf3ac00574cf10a38 upstream. Non-overlay dynamic devicetree node removal may leave the node in the phandle cache. Subsequent calls to of_find_node_by_phandle() will incorrectly find the stale entry. Remove the node from the cache. Add paranoia checks in of_find_node_by_phandle() as a second level of defense (do not return cached node if detached, do not add node to cache if detached). Fixes: 0b3ce78e90fc ("of: cache phandle nodes to reduce cost of of_find_node_by_phandle()") Reported-by: Michael Bringmann Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Frank Rowand Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

of: of_node_get()/of_node_put() nodes held in phandle cache

2019-01-13T08:24:09+00:00

commit b8a9ac1a5b99a2fcbed19fd29d2d59270c281a31 upstream. The phandle cache contains struct device_node pointers. The refcount of the pointers was not incremented while in the cache, allowing use after free error after kfree() of the node. Add the proper increment and decrement of the use count. Fixes: 0b3ce78e90fc ("of: cache phandle nodes to reduce cost of of_find_node_by_phandle()") Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Frank Rowand Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

Merge tag 'devicetree-fixes-for-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

2018-11-09T22:41:58+00:00

Pull Devicetree fixes from Rob Herring: - Add validation of NUMA distance map to prevent crashes with bad map - Fix setting of dma_mask * tag 'devicetree-fixes-for-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: of, numa: Validate some distance map rules of/device: Really only set bus DMA mask when appropriate

of, numa: Validate some distance map rules

2018-11-08T18:44:34+00:00

Currently the NUMA distance map parsing does not validate the distance table for the distance-matrix rules 1-2 in [1]. However the arch NUMA code may enforce some of these rules, but not all. Such is the case for the arm64 port, which does not enforce the rule that the distance between separates nodes cannot equal LOCAL_DISTANCE. The patch adds the following rules validation: - distance of node to self equals LOCAL_DISTANCE - distance of separate nodes > LOCAL_DISTANCE This change avoids a yet-unresolved crash reported in [2]. A note on dealing with symmetrical distances between nodes: Validating symmetrical distances between nodes is difficult. If it were mandated in the bindings that every distance must be recorded in the table, then it would be easy. However, it isn't. In addition to this, it is also possible to record [b, a] distance only (and not [a, b]). So, when processing the table for [b, a], we cannot assert that current distance of [a, b] != [b, a] as invalid, as [a, b] distance may not be present in the table and current distance would be default at REMOTE_DISTANCE. As such, we maintain the policy that we overwrite distance [a, b] = [b, a] for b > a. This policy is different to kernel ACPI SLIT validation, which allows non-symmetrical distances (ACPI spec SLIT rules allow it). However, the distance debug message is dropped as it may be misleading (for a distance which is later overwritten). Some final notes on semantics: - It is implied that it is the responsibility of the arch NUMA code to reset the NUMA distance map for an error in distance map parsing. - It is the responsibility of the FW NUMA topology parsing (whether OF or ACPI) to enforce NUMA distance rules, and not arch NUMA code. [1] Documents/devicetree/bindings/numa.txt [2] https://www.spinics.net/lists/arm-kernel/msg683304.html Cc: stable@vger.kernel.org # 4.7 Signed-off-by: John Garry Acked-by: Will Deacon Signed-off-by: Rob Herring