On Thu, Feb 21, 2019 at 12:46 PM Krzysztof Kozlowski krzk@kernel.org wrote:
Platform driver driver_override field should not be initialized from const memory because the core later kfree() it. If driver_override is manually set later through sysfs, kfree() of old value leads to:
$ echo "new_value" > /sys/bus/platform/drivers/.../driver_override kernel BUG at ../mm/slub.c:3960! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kfree) from [<c058e8c0>] (platform_set_driver_override+0x84/0xac) (platform_set_driver_override) from [<c058e908>] (driver_override_store+0x20/0x34) (driver_override_store) from [<c031f778>] (kernfs_fop_write+0x100/0x1dc) (kernfs_fop_write) from [<c0296de8>] (__vfs_write+0x2c/0x17c) (__vfs_write) from [<c02970c4>] (vfs_write+0xa4/0x188) (vfs_write) from [<c02972e8>] (ksys_write+0x4c/0xac) (ksys_write) from [<c0101000>] (ret_fast_syscall+0x0/0x28)The clk-exynos5-subcmu driver uses override only for the purpose of creating meaningful names for children devices (matching names of power domains, e.g. DISP, MFC). The driver_override was not developed for this purpose so just switch to default names of devices to fix the issue.
Fixes: b06a532bf1fa ("clk: samsung: Add Exynos5 sub-CMU clock driver") Cc: stable@vger.kernel.org Signed-off-by: Krzysztof Kozlowski krzk@kernel.org
Reviewed-by: Geert Uytterhoeven geert+renesas@glider.be
Gr{oetje,eeting}s,
Geert