4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> commit 0fbdf9953b41c28845fe8d05007ff09634ee3000 upstream. The MMC hosts could be left in an unconsistent or uninitialized state from the firmware. Instead of assuming, the firmware did the right things, let's reset the host controllers. This change fixes a bug when the mmc2/sdio is initialized leading to a hung task: [ 242.704294] INFO: task kworker/7:1:675 blocked for more than 120 seconds. [ 242.711129] Not tainted 4.9.0-rc8-00017-gcf0251f #3 [ 242.716571] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 242.724435] kworker/7:1 D 0 675 2 0x00000000 [ 242.729973] Workqueue: events_freezable mmc_rescan [ 242.734796] Call trace: [ 242.737269] [<ffff00000808611c>] __switch_to+0xa8/0xb4 [ 242.742437] [<ffff000008d07c04>] __schedule+0x1c0/0x67c [ 242.747689] [<ffff000008d08254>] schedule+0x40/0xa0 [ 242.752594] [<ffff000008d0b284>] schedule_timeout+0x1c4/0x35c [ 242.758366] [<ffff000008d08e38>] wait_for_common+0xd0/0x15c [ 242.763964] [<ffff000008d09008>] wait_for_completion+0x28/0x34 [ 242.769825] [<ffff000008a1a9f4>] mmc_wait_for_req_done+0x40/0x124 [ 242.775949] [<ffff000008a1ab98>] mmc_wait_for_req+0xc0/0xf8 [ 242.781549] [<ffff000008a1ac3c>] mmc_wait_for_cmd+0x6c/0x84 [ 242.787149] [<ffff000008a26610>] mmc_io_rw_direct_host+0x9c/0x114 [ 242.793270] [<ffff000008a26aa0>] sdio_reset+0x34/0x7c [ 242.798347] [<ffff000008a1d46c>] mmc_rescan+0x2fc/0x360 [ ... ] Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> Signed-off-by: Wei Xu <xuwei5@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/boot/dts/hisilicon/hi6220.dtsi | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi +++ b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi @@ -772,6 +772,7 @@ clocks = <&sys_ctrl 2>, <&sys_ctrl 1>; clock-names = "ciu", "biu"; resets = <&sys_ctrl PERIPH_RSTDIS0_MMC0>; + reset-names = "reset"; bus-width = <0x8>; vmmc-supply = <&ldo19>; pinctrl-names = "default"; @@ -795,6 +796,7 @@ clocks = <&sys_ctrl 4>, <&sys_ctrl 3>; clock-names = "ciu", "biu"; resets = <&sys_ctrl PERIPH_RSTDIS0_MMC1>; + reset-names = "reset"; vqmmc-supply = <&ldo7>; vmmc-supply = <&ldo10>; bus-width = <0x4>; @@ -813,6 +815,7 @@ clocks = <&sys_ctrl HI6220_MMC2_CIUCLK>, <&sys_ctrl HI6220_MMC2_CLK>; clock-names = "ciu", "biu"; resets = <&sys_ctrl PERIPH_RSTDIS0_MMC2>; + reset-names = "reset"; bus-width = <0x4>; broken-cd; pinctrl-names = "default", "idle";