Re: ioremap vs remap_pfn_range, VMSPLIT, etc

2015-01-09 Thread Russell King - ARM Linux
On Fri, Jan 09, 2015 at 06:46:24PM +0100, Mason wrote: > On 09/01/2015 14:13, Russell King - ARM Linux wrote: > > > On Fri, Jan 09, 2015 at 01:59:10PM +0100, Mason wrote: > >> I was expecting it to fail. > >> > >> - the kernel is configured with VMSPLIT_3G (3G/1G user/kernel) > > > > This has no

Re: ioremap vs remap_pfn_range, VMSPLIT, etc

2015-01-09 Thread Mason
Hello Vladimir, On 09/01/2015 19:06, Vladimir Murzin wrote: > On 09/01/15 17:46, Mason wrote: >> On 09/01/2015 14:13, Russell King - ARM Linux wrote: >> >>> On Fri, Jan 09, 2015 at 01:59:10PM +0100, Mason wrote: >>> Yesterday, I used /dev/mem to mmap 2 GB and (to my surprise) it worked.

Re: ioremap vs remap_pfn_range, VMSPLIT, etc

2015-01-09 Thread Vladimir Murzin
On 09/01/15 17:46, Mason wrote: > On 09/01/2015 14:13, Russell King - ARM Linux wrote: > >> On Fri, Jan 09, 2015 at 01:59:10PM +0100, Mason wrote: >> >>> Yesterday, I used /dev/mem to mmap 2 GB and (to my surprise) it worked. >>> Specifically, I opened /dev/mem O_RDWR | O_SYNC >>> then called >>>

Re: ioremap vs remap_pfn_range, VMSPLIT, etc

2015-01-09 Thread Mason
On 09/01/2015 14:13, Russell King - ARM Linux wrote: > On Fri, Jan 09, 2015 at 01:59:10PM +0100, Mason wrote: > >> Yesterday, I used /dev/mem to mmap 2 GB and (to my surprise) it worked. >> Specifically, I opened /dev/mem O_RDWR | O_SYNC >> then called >> mmap(NULL, 1U<<31, PROT_WRITE, MAP_SHARE

Re: ioremap vs remap_pfn_range, VMSPLIT, etc

2015-01-09 Thread Russell King - ARM Linux
On Fri, Jan 09, 2015 at 01:59:10PM +0100, Mason wrote: > Hello everyone, > > Yesterday, I used /dev/mem to mmap 2 GB and (to my surprise) it worked. > Specifically, I opened /dev/mem O_RDWR | O_SYNC > then called > mmap(NULL, 1U<<31, PROT_WRITE, MAP_SHARED, fd, 0x8000); So you asked to map

ioremap vs remap_pfn_range, VMSPLIT, etc

2015-01-09 Thread Mason
Hello everyone, Yesterday, I used /dev/mem to mmap 2 GB and (to my surprise) it worked. Specifically, I opened /dev/mem O_RDWR | O_SYNC then called mmap(NULL, 1U<<31, PROT_WRITE, MAP_SHARED, fd, 0x8000); And mmap returned a valid pointer. I was expecting it to fail. - the kernel is config