Re: [PATCH 0/5] Remove CRYPTO_ALG_ALLOCATES_MEMORY flag

[Giovanni Cabiddu]

On Fri, Jun 09, 2023 at 05:24:04PM +0800, Herbert Xu wrote:
> On Thu, Jun 01, 2023 at 12:23:58PM +0100, Giovanni Cabiddu wrote:
> > BTW, some time ago we did an assessment of the users of
> > !CRYPTO_ALG_ALLOCATES_MEMORY and we came to the conclusion that we
> > cannot just update the documentation.
> > dm-crypt uses scatterlists with at most 4 entries. dm-integrity,
> > instead, might allocate memory for scatterlists with an arbitrary number
> > of entries.
> 
> dm-integrity shouldn't be using ALLOCATES_MEMORY at all.  It's
> using GFP_KERNEL allocations right next to the crypto operations.
If you all agree, I can send a patch to remove CRYPTO_ALG_ALLOCATES_MEMORY
from dm-integrity and update the documentation in crypto.h.

> But those are some seriously big crypto operations, 16 thousand
> 4K pages in one hit?

Regards,

-- 
Giovanni