lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 6 Mar 2020 11:27:51 +1100 (AEDT) From: Michael Ellerman <patch-notifications@...erman.id.au> To: Christophe Leroy <christophe.leroy@....fr>, Benjamin Herrenschmidt <benh@...nel.crashing.org>, Paul Mackerras <paulus@...ba.org> Cc: linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH] powerpc/mm: Don't kmap_atomic() in pte_offset_map() on PPC32 On Mon, 2020-02-17 at 09:41:35 UTC, Christophe Leroy wrote: > On PPC32, pte_offset_map() does a kmap_atomic() in order to support > page tables allocated in high memory, just like ARM and x86/32. > > But since at least 2008 and commit 8054a3428fbe ("powerpc: Remove dead > CONFIG_HIGHPTE"), page tables are never allocated in high memory. > > When the page is in low mem, kmap_atomic() just returns the page > address but still disable preemption and pagefault. And it is > not an inlined function, so we suffer function call for no reason. > > Make pte_offset_map() the same as pte_offset_kernel() and make > pte_unmap() void, in the same way as PPC64 which doesn't have HIGHMEM. > > Signed-off-by: Christophe Leroy <christophe.leroy@....fr> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/6453f9ed9d4e4b4cdf201bf34bf460c436bf50ea cheers
Powered by blists - more mailing lists