wireguard-linux/drivers/base/regmap/regcache-maple.c, branch update-toolchain

regmap: maple: work around gcc-14.1 false-positive warning

2024-07-22T12:04:04Z

With gcc-14.1, there is a false-postive -Wuninitialized warning in regcache_maple_drop: drivers/base/regmap/regcache-maple.c: In function 'regcache_maple_drop': drivers/base/regmap/regcache-maple.c:113:23: error: 'lower_index' is used uninitialized [-Werror=uninitialized] 113 | unsigned long lower_index, lower_last; | ^~~~~~~~~~~ drivers/base/regmap/regcache-maple.c:113:36: error: 'lower_last' is used uninitialized [-Werror=uninitialized] 113 | unsigned long lower_index, lower_last; | ^~~~~~~~~~ I've created a reduced test case to see if this needs to be reported as a gcc, but it appears that the gcc-14.x branch already has a change that turns this into a more sensible -Wmaybe-uninitialized warning, so I ended up not reporting it so far. The reduced test case also produces a warning for gcc-13 and gcc-12 but I don't see that with the version in the kernel. Link: https://godbolt.org/z/oKbohKqd3 Link: https://lore.kernel.org/all/CAMuHMdWj=FLmkazPbYKPevDrcym2_HDb_U7Mb9YE9ovrP0jJfA@mail.gmail.com/ Signed-off-by: Arnd Bergmann Link: https://patch.msgid.link/20240719104030.1382465-1-arnd@kernel.org Signed-off-by: Mark Brown

regmap: maple: Switch to use kmemdup_array()

2024-06-07T13:28:23Z

Let the kememdup_array() take care about multiplication and possible overflows. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20240606164717.3031107-5-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

regmap: kunit: Add some test cases and a few small

2024-04-09T22:27:14Z

Merge series from Richard Fitzgerald : This series adds some more test cases, mainly for testing: commit eaa03486d932 ("regmap: maple: Fix uninitialized symbol 'ret' warnings") commit 00bb549d7d63 ("regmap: maple: Fix cache corruption in regcache_maple_drop()") And the pending patch ("regmap: Add regmap_read_bypassed()") There are also a few small improvements to the KUnit implementation.

regmap: maple: Fix uninitialized symbol 'ret' warnings

2024-03-29T16:32:26Z

Fix warnings reported by smatch by initializing local 'ret' variable to 0. drivers/base/regmap/regcache-maple.c:186 regcache_maple_drop() error: uninitialized symbol 'ret'. drivers/base/regmap/regcache-maple.c:290 regcache_maple_sync() error: uninitialized symbol 'ret'. Signed-off-by: Richard Fitzgerald Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache") Link: https://lore.kernel.org/r/20240329144630.1965159-1-rf@opensource.cirrus.com Signed-off-by: Mark Brown

regmap: maple: Fix cache corruption in regcache_maple_drop()

2024-03-27T15:00:28Z

When keeping the upper end of a cache block entry, the entry[] array must be indexed by the offset from the base register of the block, i.e. max - mas.index. The code was indexing entry[] by only the register address, leading to an out-of-bounds access that copied some part of the kernel memory over the cache contents. This bug was not detected by the regmap KUnit test because it only tests with a block of registers starting at 0, so mas.index == 0. Signed-off-by: Richard Fitzgerald Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache") Link: https://msgid.link/r/20240327114406.976986-1-rf@opensource.cirrus.com Signed-off-by: Mark Brown

regmap: maple: Remove second semicolon

2024-03-25T00:47:58Z

There is a statement with two semicolons. Remove the second one, it is redundant. Signed-off-by: Colin Ian King Link: https://msgid.link/r/20240315084417.2427797-1-colin.i.king@gmail.com Signed-off-by: Mark Brown

regmap: maple: Use alloc_flags for memory allocations

2023-07-20T19:37:39Z

REGCACHE_MAPLE needs to allocate memory for regmap operations. This results in lockdep splats if used with fast_io since fast_io uses spinlocks for locking. BUG: sleeping function called from invalid context at include/linux/sched/mm.h:306 in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 167, name: kunit_try_catch preempt_count: 1, expected: 0 1 lock held by kunit_try_catch/167: #0: 838e9c10 (regmap_kunit:86:(config)->lock){....}-{2:2}, at: regmap_lock_spinlock+0x14/0x1c irq event stamp: 146 hardirqs last enabled at (145): [<8078bfa8>] crng_make_state+0x1a0/0x294 hardirqs last disabled at (146): [<80c5f62c>] _raw_spin_lock_irqsave+0x7c/0x80 softirqs last enabled at (0): [<80110cc4>] copy_process+0x810/0x216c softirqs last disabled at (0): [<00000000>] 0x0 CPU: 0 PID: 167 Comm: kunit_try_catch Tainted: G N 6.5.0-rc1-00028-gc4be22597a36-dirty #6 Hardware name: Generic DT based system unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x38/0x5c dump_stack_lvl from __might_resched+0x188/0x2d0 __might_resched from __kmem_cache_alloc_node+0x1f4/0x258 __kmem_cache_alloc_node from __kmalloc+0x48/0x170 __kmalloc from regcache_maple_write+0x194/0x248 regcache_maple_write from _regmap_write+0x88/0x140 _regmap_write from regmap_write+0x44/0x68 regmap_write from basic_read_write+0x8c/0x27c basic_read_write from kunit_generic_run_threadfn_adapter+0x1c/0x28 kunit_generic_run_threadfn_adapter from kthread+0xf8/0x120 kthread from ret_from_fork+0x14/0x3c Exception stack(0x881a5fb0 to 0x881a5ff8) 5fa0: 00000000 00000000 00000000 00000000 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Use map->alloc_flags instead of GFP_KERNEL for memory allocations to fix the problem. Fixes: f033c26de5a5 ("regmap: Add maple tree based register cache") Cc: Dan Carpenter Signed-off-by: Guenter Roeck Link: https://lore.kernel.org/r/20230720172021.2617326-1-linux@roeck-us.net Signed-off-by: Mark Brown

regmap: maple: Implement block sync for the maple tree cache

2023-06-12T13:51:06Z

For register maps where we can write multiple values in a single bus operation it is generally much faster to do so. Improve the performance of maple tree cache syncs on such devices by identifying blocks of adjacent registers that need to be written out and combining them into a single operation. Combining writes does mean that we need to allocate a scratch buffer and format the data into it but it is expected that for most cases where caches are in use the cost of I/O will be much greater than the cost of doing the allocation and format. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230609-regcache-maple-sync-raw-v1-1-8ddeb4e2b9ab@kernel.org Signed-off-by: Mark Brown

regmap: Merge up v6.4-rc6

2023-06-12T13:50:15Z

The fix for maple tree RCU locking on sync is a dependency for the block sync code for the maple tree.

regmap: Load register defaults in blocks rather than register by register

2023-05-24T10:21:56Z

Currently we use the normal single register write function to load the default values into the cache, resulting in a large number of reallocations when there are blocks of registers as we extend the memory region we are using to store the values. Instead scan through the list of defaults for blocks of adjacent registers and do a single allocation and insert for each such block. No functional change. We do not take advantage of the maple tree preallocation, this is purely at the regcache level. It is not clear to me yet if the maple tree level would help much here or if we'd have more overhead from overallocating and then freeing maple tree data. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20230523-regcache-maple-load-defaults-v1-1-0c04336f005d@kernel.org Signed-off-by: Mark Brown