Date: Mon, 13 Nov 2017 14:46:25 -0800 From: Dave Hansen <dave.hansen@...el.com> To: Tycho Andersen <tycho@...ker.com> Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org, kernel-hardening@...ts.openwall.com, Marco Benatto <marco.antonio.780@...il.com>, Juerg Haefliger <juerg.haefliger@...onical.com>, x86@...nel.org Subject: Re: [PATCH v6 03/11] mm, x86: Add support for eXclusive Page Frame Ownership (XPFO) On 11/13/2017 02:20 PM, Dave Hansen wrote: > On 11/09/2017 05:09 PM, Tycho Andersen wrote: >> which I guess is from the additional flags in grow_dev_page() somewhere down >> the stack. Anyway... it seems this is a kernel allocation that's using >> MIGRATE_MOVABLE, so perhaps we need some more fine tuned heuristic than just >> all MOVABLE allocations are un-mapped via xpfo, and all the others are mapped. >> >> Do you have any ideas? > > It still has to do a kmap() or kmap_atomic() to be able to access it. I > thought you hooked into that. Why isn't that path getting hit for these? Oh, this looks to be accessing data mapped by a buffer_head. It (rudely) accesses data via: void set_bh_page(struct buffer_head *bh, ... bh->b_data = page_address(page) + offset;
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.