What commit do you refer here to? From googling the hash I guess it is
some kind of a kernel patch, but maybe you can clarify a little?
I just searched the kernel git source - so this git commit was accepted
into kernel source in 2014.
A quick look at diff it refers to a file in drivers/block/nvme-core.c
which no longer exists.
Looks like code was moved and plenty of changes. I find in drivers/nvme
that :
host/core.c:static unsigned char shutdown_timeout = 5;
host/core.c:MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for
controller shutdown");
which suggests the current default is 5 seconds to wait for h/w to ack -
maybe some h/w needs more than 5 secs ...
As I said, not an expert, but I'm definitely curious but not concerned.
I have no actual evidence of cache flushes not being on disk. Not saying
there are none - just I've not been aware of any.
About all I know at this point :)
gene