Re: [ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-13 Thread Nicolas Pitre
On Thu, 13 Mar 2014, Liu hua wrote: > On 2014/3/13 1:08, Nicolas Pitre wrote: > > On Wed, 12 Mar 2014, Liu hua wrote: > > > >> Hi Russell, Will or Nicolas, > >> > >> (In this mail, we only discuss ARM 32-bit linux.) > >> > >> As we know, the region (0xfff0-0xfffd) is reserved as fixmap >

Re: [ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-13 Thread Liu hua
On 2014/3/13 1:08, Nicolas Pitre wrote: > On Wed, 12 Mar 2014, Liu hua wrote: > >> Hi Russell, Will or Nicolas, >> >> (In this mail, we only discuss ARM 32-bit linux.) >> >> As we know, the region (0xfff0-0xfffd) is reserved as fixmap >> mapping region. >> >> The function "kmap_atomic"

Re: [ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-13 Thread Liu hua
On 2014/3/13 1:08, Nicolas Pitre wrote: On Wed, 12 Mar 2014, Liu hua wrote: Hi Russell, Will or Nicolas, (In this mail, we only discuss ARM 32-bit linux.) As we know, the region (0xfff0-0xfffd) is reserved as fixmap mapping region. The function kmap_atomic maps highmem pages to

Re: [ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-13 Thread Nicolas Pitre
On Thu, 13 Mar 2014, Liu hua wrote: On 2014/3/13 1:08, Nicolas Pitre wrote: On Wed, 12 Mar 2014, Liu hua wrote: Hi Russell, Will or Nicolas, (In this mail, we only discuss ARM 32-bit linux.) As we know, the region (0xfff0-0xfffd) is reserved as fixmap mapping region.

Re: [ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-12 Thread Nicolas Pitre
On Wed, 12 Mar 2014, Liu hua wrote: > Hi Russell, Will or Nicolas, > > (In this mail, we only discuss ARM 32-bit linux.) > > As we know, the region (0xfff0-0xfffd) is reserved as fixmap > mapping region. > > The function "kmap_atomic" maps highmem pages to this region referring > to

[ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-12 Thread Liu hua
Hi Russell, Will or Nicolas, (In this mail, we only discuss ARM 32-bit linux.) As we know, the region (0xfff0-0xfffd) is reserved as fixmap mapping region. The function "kmap_atomic" maps highmem pages to this region referring to CPUID and per-cpu variable "__kmap_atomic_idx" via idx

Re: [ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-12 Thread Nicolas Pitre
On Wed, 12 Mar 2014, Liu hua wrote: Hi Russell, Will or Nicolas, (In this mail, we only discuss ARM 32-bit linux.) As we know, the region (0xfff0-0xfffd) is reserved as fixmap mapping region. The function kmap_atomic maps highmem pages to this region referring to CPUID and

[ARM]Fixmap mapping region is not enough for system of 14+ CPUs.

2014-03-12 Thread Liu hua
Hi Russell, Will or Nicolas, (In this mail, we only discuss ARM 32-bit linux.) As we know, the region (0xfff0-0xfffd) is reserved as fixmap mapping region. The function kmap_atomic maps highmem pages to this region referring to CPUID and per-cpu variable __kmap_atomic_idx via idx =