|
Message-ID: <CAJZ5v0hE7ND5y-q+o-M9ck05VFDKWkBYJ-=3C2ZRn_aw5o4y+Q@mail.gmail.com> Date: Mon, 8 Aug 2016 15:54:48 +0200 From: "Rafael J. Wysocki" <rafael@...nel.org> To: Borislav Petkov <bp@...e.de> Cc: "Rafael J. Wysocki" <rjw@...ysocki.net>, Linux PM list <linux-pm@...r.kernel.org>, Thomas Garnier <thgarnie@...gle.com>, "the arch/x86 maintainers" <x86@...nel.org>, Linux Kernel Mailing List <linux-kernel@...r.kernel.org>, Yinghai Lu <yinghai@...nel.org>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, "H . Peter Anvin" <hpa@...or.com>, Kees Cook <keescook@...omium.org>, Pavel Machek <pavel@....cz>, Kernel Hardening <kernel-hardening@...ts.openwall.com>, Borislav Petkov <bpetkov@...e.de> Subject: Re: [Resend][PATCH] x86/power/64: Always create temporary identity mapping correctly On Mon, Aug 8, 2016 at 3:40 PM, Borislav Petkov <bp@...e.de> wrote: > On Mon, Aug 08, 2016 at 03:31:31PM +0200, Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki <rafael.j.wysocki@...el.com> >> >> The low-level resume-from-hibernation code on x86-64 uses >> kernel_ident_mapping_init() to create the temoprary identity mapping, >> but that function assumes that the offset between kernel virtual >> addresses and physical addresses is aligned on the PGD level. >> >> However, with a randomized identity mapping base, it may be aligned >> on the PUD level and if that happens, the temporary identity mapping >> created by set_up_temporary_mappings() will not reflect the actual >> kernel identity mapping and the image restoration will fail as a >> result (leading to a kernel panic most of the time). >> >> To fix this problem, rework kernel_ident_mapping_init() to support >> unaligned offsets between KVA and PA up to the PMD level and make >> set_up_temporary_mappings() use it as approprtiate. >> >> Reported-by: Thomas Garnier <thgarnie@...gle.com> > > Reported-by: Borislav Petkov <bp@...e.de> > >> Suggested-by: Yinghai Lu <yinghai@...nel.org> >> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com> >> Acked-by: Yinghai Lu <yinghai@...nel.org> >> --- >> >> This is sort of urgent, because hibernation doesn't work with KASLR on x86-64 >> in 4.8-rc1 AFAICS and this should make them work together again. >> >> Unless anyone sees any problems with it, I'll queue it up for 4.8-rc2. >> >> Thomas, would it be possible to test it with KASLR enabled, please? > > Is that the only patch which needs to be tested? Ontop of which tree? That should be the only one on top of plain 4.8-rc1. If it doesn't help, we need more work to do. :-) > CONFIG_RANDOMIZE_MEMORY blew up s2d on my laptop here so I'll run it > once I have the required info from you :) Thanks! Best, Rafael
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.