Re: [PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-17 Thread Peter Zijlstra
On Tue, Jan 16, 2018 at 02:51:45PM -0800, Andy Lutomirski wrote: > On Tue, Jan 16, 2018 at 8:52 AM, Peter Zijlstra wrote: > > On Tue, Jan 16, 2018 at 05:36:49PM +0100, Joerg Roedel wrote: > >> From: Joerg Roedel > >> > >> Reserve 2MB/4MB of address space for mapping the LDT to > >> user-space. >

Re: [PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-16 Thread Andy Lutomirski
On Tue, Jan 16, 2018 at 8:52 AM, Peter Zijlstra wrote: > On Tue, Jan 16, 2018 at 05:36:49PM +0100, Joerg Roedel wrote: >> From: Joerg Roedel >> >> Reserve 2MB/4MB of address space for mapping the LDT to >> user-space. > > LDT is 64k, we need 2 per CPU, and NR_CPUS <= 64 on 32bit, that gives > 64K

Re: [PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-16 Thread Waiman Long
On 01/16/2018 12:31 PM, Peter Zijlstra wrote: > On Tue, Jan 16, 2018 at 06:13:43PM +0100, Joerg Roedel wrote: >> Hi Peter, >> >> On Tue, Jan 16, 2018 at 05:52:13PM +0100, Peter Zijlstra wrote: >>> On Tue, Jan 16, 2018 at 05:36:49PM +0100, Joerg Roedel wrote: From: Joerg Roedel Reser

Re: [PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-16 Thread Peter Zijlstra
On Tue, Jan 16, 2018 at 06:13:43PM +0100, Joerg Roedel wrote: > Hi Peter, > > On Tue, Jan 16, 2018 at 05:52:13PM +0100, Peter Zijlstra wrote: > > On Tue, Jan 16, 2018 at 05:36:49PM +0100, Joerg Roedel wrote: > > > From: Joerg Roedel > > > > > > Reserve 2MB/4MB of address space for mapping the LD

Re: [PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-16 Thread Joerg Roedel
Hi Peter, On Tue, Jan 16, 2018 at 05:52:13PM +0100, Peter Zijlstra wrote: > On Tue, Jan 16, 2018 at 05:36:49PM +0100, Joerg Roedel wrote: > > From: Joerg Roedel > > > > Reserve 2MB/4MB of address space for mapping the LDT to > > user-space. > > LDT is 64k, we need 2 per CPU, and NR_CPUS <= 64 o

Re: [PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-16 Thread Peter Zijlstra
On Tue, Jan 16, 2018 at 05:36:49PM +0100, Joerg Roedel wrote: > From: Joerg Roedel > > Reserve 2MB/4MB of address space for mapping the LDT to > user-space. LDT is 64k, we need 2 per CPU, and NR_CPUS <= 64 on 32bit, that gives 64K*2*64=8M > 2M.

[PATCH 06/16] x86/mm/ldt: Reserve high address-space range for the LDT

2018-01-16 Thread Joerg Roedel
From: Joerg Roedel Reserve 2MB/4MB of address space for mapping the LDT to user-space. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/pgtable_32_types.h | 5 - 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm