Re: [PATCH 09/16] ps3disk: use memcpy_{from,to}_bvec

On Fri, Jun 11, 2021 at 09:07:43PM -0700, Ira Weiny wrote:

More recently this was added:

7e34e0bbc644 crypto: omap-crypto - fix userspace copied buffer access

I'm CC'ing Tero and Herbert to see why they added the SLAB check.

Probably because the generic Crypto API has the same check.  This
all goes back to

commit 4f3e797ad07d52d34983354a77b365dfcd48c1b4
Author: Herbert Xu [off-list ref]
Date:   Mon Feb 9 14:22:14 2009 +1100

    crypto: scatterwalk - Avoid flush_dcache_page on slab pages

    It's illegal to call flush_dcache_page on slab pages on a number
    of architectures.  So this patch avoids doing so if PageSlab is
    true.

    In future we can move the flush_dcache_page call to those page
    cache users that actually need it.

    Reported-by: David S. Miller [off-list ref]
    Signed-off-by: Herbert Xu [off-list ref]

But I can't find any emails discussing this so let me ask Dave
directly and see if he can tell us what the issue was or might
have been.

Thanks,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt