Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/14/2018 01:00 AM, Florian Weimer wrote: > ... but not the key which is used for PROT_EXEC emulation, which is still > reserved The PROT_EXEC key is dynamically allocated. There is no "the key".

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/14/2018 01:00 AM, Florian Weimer wrote: > ... but not the key which is used for PROT_EXEC emulation, which is still > reserved The PROT_EXEC key is dynamically allocated. There is no "the key".

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/14/2018 09:00 AM, Florian Weimer wrote: On 03/09/2018 09:00 PM, Ram Pai wrote: On Fri, Mar 09, 2018 at 12:04:49PM +0100, Florian Weimer wrote: On 03/09/2018 09:12 AM, Ram Pai wrote: Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/14/2018 09:00 AM, Florian Weimer wrote: On 03/09/2018 09:00 PM, Ram Pai wrote: On Fri, Mar 09, 2018 at 12:04:49PM +0100, Florian Weimer wrote: On 03/09/2018 09:12 AM, Ram Pai wrote: Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 09:00 PM, Ram Pai wrote: On Fri, Mar 09, 2018 at 12:04:49PM +0100, Florian Weimer wrote: On 03/09/2018 09:12 AM, Ram Pai wrote: Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is no valid reason for the above behavior.

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 09:00 PM, Ram Pai wrote: On Fri, Mar 09, 2018 at 12:04:49PM +0100, Florian Weimer wrote: On 03/09/2018 09:12 AM, Ram Pai wrote: Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is no valid reason for the above behavior.

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 12:06 PM, Ram Pai wrote: > On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote: >> Ram Pai writes: >> >>> Once an address range is associated with an allocated pkey, it cannot be >>> reverted back to key-0. There is no valid reason for the above

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 12:06 PM, Ram Pai wrote: > On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote: >> Ram Pai writes: >> >>> Once an address range is associated with an allocated pkey, it cannot be >>> reverted back to key-0. There is no valid reason for the above behavior. On >>> the

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 09:55 PM, Ram Pai wrote: > On Fri, Mar 09, 2018 at 02:40:32PM -0800, Dave Hansen wrote: >> On 03/09/2018 12:12 AM, Ram Pai wrote: >>> Once an address range is associated with an allocated pkey, it cannot be >>> reverted back to key-0. There is no valid reason for the above behavior.

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 09:55 PM, Ram Pai wrote: > On Fri, Mar 09, 2018 at 02:40:32PM -0800, Dave Hansen wrote: >> On 03/09/2018 12:12 AM, Ram Pai wrote: >>> Once an address range is associated with an allocated pkey, it cannot be >>> reverted back to key-0. There is no valid reason for the above behavior.

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 02:40:32PM -0800, Dave Hansen wrote: > On 03/09/2018 12:12 AM, Ram Pai wrote: > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications need the

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 02:40:32PM -0800, Dave Hansen wrote: > On 03/09/2018 12:12 AM, Ram Pai wrote: > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications need the

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 12:12 AM, Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. Why don't we just set pkey 0 to be allocated in

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 12:12 AM, Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. Why don't we just set pkey 0 to be allocated in

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 09:43:32AM +0100, Ingo Molnar wrote: > > * Ram Pai wrote: > > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 09:43:32AM +0100, Ingo Molnar wrote: > > * Ram Pai wrote: > > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications need the ability to do

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote: > Ram Pai writes: > > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 09:19:53PM +1100, Michael Ellerman wrote: > Ram Pai writes: > > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary applications need the ability to do

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 12:04:49PM +0100, Florian Weimer wrote: > On 03/09/2018 09:12 AM, Ram Pai wrote: > >Once an address range is associated with an allocated pkey, it cannot be > >reverted back to key-0. There is no valid reason for the above behavior. > > mprotect without a key does not

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 12:04:49PM +0100, Florian Weimer wrote: > On 03/09/2018 09:12 AM, Ram Pai wrote: > >Once an address range is associated with an allocated pkey, it cannot be > >reverted back to key-0. There is no valid reason for the above behavior. > > mprotect without a key does not

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 07:37:04PM +1100, Balbir Singh wrote: > On Fri, Mar 9, 2018 at 7:12 PM, Ram Pai wrote: > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 09, 2018 at 07:37:04PM +1100, Balbir Singh wrote: > On Fri, Mar 9, 2018 at 7:12 PM, Ram Pai wrote: > > Once an address range is associated with an allocated pkey, it cannot be > > reverted back to key-0. There is no valid reason for the above behavior. On > > the contrary

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 09:12 AM, Ram Pai wrote: Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is no valid reason for the above behavior. mprotect without a key does not necessarily use key 0, e.g. if protection keys are used to emulate page

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On 03/09/2018 09:12 AM, Ram Pai wrote: Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is no valid reason for the above behavior. mprotect without a key does not necessarily use key 0, e.g. if protection keys are used to emulate page

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

Ram Pai writes: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. Please explain this in much more detail. Is it an

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

Ram Pai writes: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. Please explain this in much more detail. Is it an ABI change? And why

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

* Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. > > The patch relaxes the restriction. > >

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

* Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. > > The patch relaxes the restriction. > > Tested on powerpc and

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 9, 2018 at 7:12 PM, Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. > > The patch

Re: [PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

On Fri, Mar 9, 2018 at 7:12 PM, Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. > > The patch relaxes the restriction. I

[PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is no valid reason for the above behavior. On the contrary applications need the ability to do so. The patch relaxes the restriction. Tested on powerpc and x86_64. cc: Dave Hansen

[PATCH] x86, powerpc : pkey-mprotect must allow pkey-0

Once an address range is associated with an allocated pkey, it cannot be reverted back to key-0. There is no valid reason for the above behavior. On the contrary applications need the ability to do so. The patch relaxes the restriction. Tested on powerpc and x86_64. cc: Dave Hansen cc: