On 08/13/2017 12:44 PM, Christoph Hellwig wrote:
> Defaulting to scsi-mq in 4.13-rc has shown various regressions
> on setups that we didn't previously consider. Fixes for them are
> in progress, but too invasive to make it in this cycle. So for
> now revert the commit that defaults to blk-mq for SCSI. For 4.14
> we'll plan to try again with these fixes.
I'm not sure if this is one of your known regressions, but I've had a
problem on my Lenovo T410 with the 4.13-rc kernels. When unplugging the
power cord, the hard disk gets suspended.
[ 1499.629415] thinkpad_acpi: EC reports that Thermal Table has changed
[ 1499.832116] sd 0:0:0:0: [sda] Synchronizing SCSI cache
[ 1499.885831] e1000e: eth0 NIC Link is Down
[ 1499.897531] sd 0:0:0:0: [sda] Stopping disk
[ 1499.923736] EXT4-fs (sda5): re-mounted. Opts: data=ordered,commit=600
[ 1504.240444] thinkpad_acpi: EC reports that Thermal Table has changed
[ 1515.502561] sd 0:0:0:0: timing out command, waited 15s
Adding "scsi_mod.use_blk_mq=0" to the command line fixes it.
Thanks,
Shaggy
>
> This reverts commit 5c279bd9e40624f4ab6e688671026d6005b066fa.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> drivers/scsi/Kconfig | 11 +++++++++++
> drivers/scsi/scsi.c | 4 ++++
> 2 files changed, 15 insertions(+)
>
> diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
> index f4538d7a3016..d145e0d90227 100644
> --- a/drivers/scsi/Kconfig
> +++ b/drivers/scsi/Kconfig
> @@ -47,6 +47,17 @@ config SCSI_NETLINK
> default n
> depends on NET
>
> +config SCSI_MQ_DEFAULT
> + bool "SCSI: use blk-mq I/O path by default"
> + depends on SCSI
> + ---help---
> + This option enables the new blk-mq based I/O path for SCSI
> + devices by default. With the option the scsi_mod.use_blk_mq
> + module/boot option defaults to Y, without it to N, but it can
> + still be overridden either way.
> +
> + If unsure say N.
> +
> config SCSI_PROC_FS
> bool "legacy /proc/scsi/ support"
> depends on SCSI && PROC_FS
> diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
> index 3d38c6d463b8..1bf274e3b2b6 100644
> --- a/drivers/scsi/scsi.c
> +++ b/drivers/scsi/scsi.c
> @@ -800,7 +800,11 @@ MODULE_LICENSE("GPL");
> module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR);
> MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels");
>
> +#ifdef CONFIG_SCSI_MQ_DEFAULT
> bool scsi_use_blk_mq = true;
> +#else
> +bool scsi_use_blk_mq = false;
> +#endif
> module_param_named(use_blk_mq, scsi_use_blk_mq, bool, S_IWUSR | S_IRUGO);
>
> static int __init init_scsi(void)
>
