Re: [LKP] [x86/mm/ASLR] f47233c2d34: WARNING: CPU: 0 PID: 1 at arch/x86/mm/ioremap.c:63 __ioremap_check_ram+0x445/0x4a0()

2015-02-28 Thread Borislav Petkov
On Sat, Feb 28, 2015 at 07:20:09PM +, Matt Fleming wrote: > Doing a static allocation is fine, and the memory is even reserved from > being overwritten via memblock_x86_reserve_range_setup_data(), but it First of all, the naming of that function has failed really badly somewhere along the way.

Re: [LKP] [x86/mm/ASLR] f47233c2d34: WARNING: CPU: 0 PID: 1 at arch/x86/mm/ioremap.c:63 __ioremap_check_ram+0x445/0x4a0()

2015-02-28 Thread Matt Fleming
On Sat, 28 Feb, at 11:50:49AM, Borislav Petkov wrote: > > Yeah, too many hmms means this still needed staring at to find out what > exactly the problem is. And the problem is that allocating that struct > setup_data statically in arch/x86/boot/compressed/aslr.c works only by > chance, when the ker

Re: [LKP] [x86/mm/ASLR] f47233c2d34: WARNING: CPU: 0 PID: 1 at arch/x86/mm/ioremap.c:63 __ioremap_check_ram+0x445/0x4a0()

2015-02-28 Thread Borislav Petkov
On Thu, Feb 26, 2015 at 01:16:17PM +0100, Borislav Petkov wrote: > The proper fix should be to say, don't ioremap setup_data which is > kernel memory but I'm not sure I have a good idea at the moment how to > do that *without* ioremapping the thing to inspect it first... > > More hmm... Yeah, too

Re: [LKP] [x86/mm/ASLR] f47233c2d34: WARNING: CPU: 0 PID: 1 at arch/x86/mm/ioremap.c:63 __ioremap_check_ram+0x445/0x4a0()

2015-02-26 Thread Borislav Petkov
On Thu, Feb 26, 2015 at 12:12:50PM +0100, Ingo Molnar wrote: > Why is it ioremap()-ed to begin with, why cannot the kernel > access its own data structure in RAM directly? Probably because those setup_data structs refer to !RAM objects and there we need to ioremap. But from looking at arch/x86/ke

Re: [LKP] [x86/mm/ASLR] f47233c2d34: WARNING: CPU: 0 PID: 1 at arch/x86/mm/ioremap.c:63 __ioremap_check_ram+0x445/0x4a0()

2015-02-26 Thread Ingo Molnar
* Borislav Petkov wrote: > thanks for the report. > > So, AFAICT, this is caused by ksysfs ioremapping struct > setup_data for a short time so that it can count it and > show it in /sys/kernel/boot_params/setup_data/* > > And, of course, the setup_data thing which we're using > for kaslr pa

Re: [LKP] [x86/mm/ASLR] f47233c2d34: WARNING: CPU: 0 PID: 1 at arch/x86/mm/ioremap.c:63 __ioremap_check_ram+0x445/0x4a0()

2015-02-26 Thread Borislav Petkov
Hi, On Thu, Feb 26, 2015 at 01:37:01PM +0800, Huang Ying wrote: > FYI, we noticed the below changes on > > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > commit f47233c2d34f243ecdaac179c3408a39ff9216a7 ("x86/mm/ASLR: Propagate base > load address calculation") > > >