Re: [PATCH 0/8] __vmalloc() and no-block support

[Marco Elver <elver@google.com>]

On Thu, Aug 07, 2025 at 09:58AM +0200, Uladzislau Rezki (Sony) wrote:
> Hello.
> 
> This is a second series of making __vmalloc() to support GFP_ATOMIC and
> GFP_NOWAIT flags. It tends to improve the non-blocking behaviour.
> 
> The first one can be found here:
> 
> https://lore.kernel.org/all/20250704152537.55724-1-urezki@gmail.com/
> 
> that was an RFC. Using this series for testing i have not found more
> places which can trigger: scheduling during atomic. Though there is
> one which requires attention. I will explain in [1].
> 
> Please note, non-blocking gets improved in the __vmalloc() call only,
> i.e. vmalloc_huge() still contains in its paths many cond_resched()
> points and can not be used as non-blocking as of now.
> 
> [1] The vmap_pages_range_noflush() contains the kmsan_vmap_pages_range_noflush()
> external implementation for KCSAN specifically which is hard coded to GFP_KERNEL.
> The kernel should be built with CONFIG_KCSAN option. To me it looks like not
> straight forward to run such kernel on my box, therefore i need more time to
> investigate what is wrong with CONFIG_KCSAN and my env.

KMSAN or KCSAN?

[+Cc KMSAN maintainers]