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[ Upstream commit9177514ce3] The change corrects registration and deregistration on error path of a regulator, the problem was manifested by a reported memory leak on deferred probe: as3722-regulator as3722-regulator: regulator 13 register failed -517 # cat /sys/kernel/debug/kmemleak unreferenced object 0xecc43740 (size 64): comm "swapper/0", pid 1, jiffies 4294937640 (age 712.880s) hex dump (first 32 bytes): 72 65 67 75 6c 61 74 6f 72 2e 32 34 00 5a 5a 5a regulator.24.ZZZ 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ backtrace: [<0c4c3d1c>] __kmalloc_track_caller+0x15c/0x2c0 [<40c0ad48>] kvasprintf+0x64/0xd4 [<109abd29>] kvasprintf_const+0x70/0x84 [<c4215946>] kobject_set_name_vargs+0x34/0xa8 [<62282ea2>] dev_set_name+0x40/0x64 [<a39b6757>] regulator_register+0x3a4/0x1344 [<16a9543f>] devm_regulator_register+0x4c/0x84 [<51a4c6a1>] as3722_regulator_probe+0x294/0x754 ... The memory leak problem was introduced as a side ef another fix in regulator_register() error path, I believe that the proper fix is to decouple device_register() function into its two compounds and initialize a struct device before assigning any values to its fields and then using it before actual registration of a device happens. This lets to call put_device() safely after initialization, and, since now a release callback is called, kfree(rdev->constraints) shall be removed to exclude a double free condition. Fixes:a3cde9534e("regulator: core: fix regulator_register() error paths to properly release rdev") Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Cc: Wen Yang <wenyang@linux.alibaba.com> Link: https://lore.kernel.org/r/20200724005013.23278-1-vz@mleia.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
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