From: "ping.gao" <ping.gao@samsung.com>
To: jh80.chung@samsung.com, sebastian.reichel@collabora.com,
shawn.lin@rock-chips.com, ulf.hansson@linaro.org,
linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
hy50.seo@samsung.com, kwangwon.min@samsung.com,
ping.gao@samsung.com
Subject: [PATCH] drivers: clk: keystone: Fix parameter judgment in clk_prepare
Date: Wed, 21 Jan 2026 15:05:03 +0800 [thread overview]
Message-ID: <20260121070503.100283-1-ping.gao@samsung.com> (raw)
In-Reply-To: CGME20260121070041epcas5p4687d60f28911c7e97497a80adb87232c@epcas5p4.samsung.com
The clk may return NULL or an ERR_PTR. Don't
treat an ERR_PTR as valid.
for example: biu_clk in dwmmc driver request fail, but it's ERR_PTR, not null , it will panic when call clk_prepare
log is below:
[ 438.400868] [7: binder:436_2: 4998] Unable to handle kernel paging request at virtual address fffffffffffffffe
[ 438.400877] [7: binder:436_2: 4998] Mem abort info:
[ 438.400881] [7: binder:436_2: 4998] ESR = 0x0000000096000005
[ 438.400887] [7: binder:436_2: 4998] EC = 0x25: DABT (current EL), IL = 32 bits
[ 438.400894] [7: binder:436_2: 4998] SET = 0, FnV = 0
[ 438.400899] [7: binder:436_2: 4998] EA = 0, S1PTW = 0
[ 438.400904] [7: binder:436_2: 4998] FSC = 0x05: level 1 translation fault
...
[ 438.409424] [7: binder:436_2: 4998] Call trace:
[ 438.409429] [7: binder:436_2: 4998] clk_prepare+0x10/0x24
[ 438.409439] [7: binder:436_2: 4998] dw_mci_runtime_resume+0x50/0x2d8 [dw_mmc_samsung cd210e210975263404c28fc89778f369f8398f0c]
[ 438.409471] [7: binder:436_2: 4998] dw_mci_exynos_runtime_resume+0x18/0x58 [dw_mmc_exynos_samsung 2735a594c7c9c9e8c65b0b87523fbf70dcaabfff]
[ 438.409496] [7: binder:436_2: 4998] pm_generic_runtime_resume+0x40/0x58
[ 438.409506] [7: binder:436_2: 4998] pm_runtime_force_resume+0x9c/0x134
[ 438.409517] [7: binder:436_2: 4998] platform_pm_resume+0x40/0x8c
[ 438.409529] [7: binder:436_2: 4998] dpm_run_callback+0x64/0x230
[ 438.409540] [7: binder:436_2: 4998] __device_resume+0x1d8/0x394
[ 438.409551] [7: binder:436_2: 4998] dpm_resume+0x110/0x2b8
[ 438.409561] [7: binder:436_2: 4998] dpm_resume_end+0x1c/0x38
[ 438.409570] [7: binder:436_2: 4998] suspend_devices_and_enter+0x828/0xab0
[ 438.409582] [7: binder:436_2: 4998] pm_suspend+0x334/0x618
[ 438.409592] [7: binder:436_2: 4998] state_store+0x104/0x144
[ 438.409601] [7: binder:436_2: 4998] kobj_attr_store+0x30/0x48
[ 438.409610] [7: binder:436_2: 4998] sysfs_kf_write+0x54/0x6c
[ 438.409619] [7: binder:436_2: 4998] kernfs_fop_write_iter+0x104/0x1a8
[ 438.409628] [7: binder:436_2: 4998] vfs_write+0x24c/0x2f4
[ 438.409640] [7: binder:436_2: 4998] ksys_write+0x78/0xe8
[ 438.409652] [7: binder:436_2: 4998] __arm64_sys_write+0x1c/0x2c
[ 438.409664] [7: binder:436_2: 4998] invoke_syscall+0x58/0x114
[ 438.409676] [7: binder:436_2: 4998] el0_svc_common+0xac/0xe0
[ 438.409687] [7: binder:436_2: 4998] do_el0_svc+0x1c/0x28
[ 438.409698] [7: binder:436_2: 4998] el0_svc+0x38/0x68
[ 438.409705] [7: binder:436_2: 4998] el0t_64_sync_handler+0x68/0xbc
[ 438.409712] [7: binder:436_2: 4998] el0t_64_sync+0x1a8/0x1ac
Signed-off-by: ping.gao <ping.gao@samsung.com>
---
drivers/clk/clk.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 85d2f2481acf..6d62f69323b5 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1171,7 +1171,7 @@ static int clk_core_prepare_lock(struct clk_core *core)
*/
int clk_prepare(struct clk *clk)
{
- if (!clk)
+ if (IS_ERR_OR_NULL(clk))
return 0;
return clk_core_prepare_lock(clk->core);
--
2.50.1
next parent reply other threads:[~2026-01-21 7:00 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20260121070041epcas5p4687d60f28911c7e97497a80adb87232c@epcas5p4.samsung.com>
2026-01-21 7:05 ` ping.gao [this message]
2026-01-22 17:56 ` [PATCH] drivers: clk: keystone: Fix parameter judgment in clk_prepare Ulf Hansson
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