Re: I/O error on cache device can cause user observable errors

[Coly Li <colyli@suse.de>]

> 2024年2月3日 01:48，Arnaldo Montagner <armont@google.com> 写道：
> 
> Thanks for clarifying.
> 
> Regarding the documentation, the first sentence in
> https://docs.kernel.org/admin-guide/bcache.html#error-handling says:
> "Bcache tries to transparently handle IO errors to/from the cache
> device without affecting normal operation"
> 

Oh I see. This is for temporary I/O failure or error. If cache is clear and an I/O error encountered, bcache may fetch data from backing device.
Such operations are transparent to upper layer code.

> I guess I interpreted it in absolute terms, as some kind of guarantee
> that normal operation would not be affected.
> 

For devices failure or absence, bcache need to make upper layer code to be aware and hand the aftermath when necessary. Your situation is in this category.

Thanks.

Coly Li