Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Michael Kerrisk (man-pages)
Hi Mike, On 25 September 2017 at 18:33, Mike Kravetz wrote: > On 09/20/2017 12:25 AM, Michael Kerrisk (man-pages) wrote: [...] >> I've applied this, and added Reviewed-by tags for Florian and Jann. >> But, I think it's also worth noting the older, now disallowed,

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Michael Kerrisk (man-pages)
Hi Mike, On 25 September 2017 at 18:33, Mike Kravetz wrote: > On 09/20/2017 12:25 AM, Michael Kerrisk (man-pages) wrote: [...] >> I've applied this, and added Reviewed-by tags for Florian and Jann. >> But, I think it's also worth noting the older, now disallowed, behavior, >> and why the

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Mike Kravetz
On 09/20/2017 12:25 AM, Michael Kerrisk (man-pages) wrote: > Hello Mike, > > On 09/19/2017 11:42 PM, Mike Kravetz wrote: >> v2: Fix incorrect wording noticed by Jann Horn. >> Remove deprecated and memfd_create discussion as suggested >> by Florian Weimer. >> >> Since at least the 2.6 time

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Mike Kravetz
On 09/20/2017 12:25 AM, Michael Kerrisk (man-pages) wrote: > Hello Mike, > > On 09/19/2017 11:42 PM, Mike Kravetz wrote: >> v2: Fix incorrect wording noticed by Jann Horn. >> Remove deprecated and memfd_create discussion as suggested >> by Florian Weimer. >> >> Since at least the 2.6 time

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Michael Kerrisk (man-pages)
On 25 September 2017 at 14:36, Michal Hocko wrote: > On Wed 20-09-17 09:25:42, Michael Kerrisk wrote: > [...] >> BUGS >>Before Linux 4.14, if old_size was zero and the mapping referred >>to by old_address was a private mapping (mmap(2) MAP_PRIVATE), >>

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Michael Kerrisk (man-pages)
On 25 September 2017 at 14:36, Michal Hocko wrote: > On Wed 20-09-17 09:25:42, Michael Kerrisk wrote: > [...] >> BUGS >>Before Linux 4.14, if old_size was zero and the mapping referred >>to by old_address was a private mapping (mmap(2) MAP_PRIVATE), >>mremap()

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Michal Hocko
On Wed 20-09-17 09:25:42, Michael Kerrisk wrote: [...] > BUGS >Before Linux 4.14, if old_size was zero and the mapping referred >to by old_address was a private mapping (mmap(2) MAP_PRIVATE), >mremap() created a new private mapping unrelated to the original >

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-25 Thread Michal Hocko
On Wed 20-09-17 09:25:42, Michael Kerrisk wrote: [...] > BUGS >Before Linux 4.14, if old_size was zero and the mapping referred >to by old_address was a private mapping (mmap(2) MAP_PRIVATE), >mremap() created a new private mapping unrelated to the original >

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-20 Thread Michael Kerrisk (man-pages)
Hello Mike, On 09/19/2017 11:42 PM, Mike Kravetz wrote: > v2: Fix incorrect wording noticed by Jann Horn. > Remove deprecated and memfd_create discussion as suggested > by Florian Weimer. > > Since at least the 2.6 time frame, mremap would create a new mapping > of the same pages if

Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-20 Thread Michael Kerrisk (man-pages)
Hello Mike, On 09/19/2017 11:42 PM, Mike Kravetz wrote: > v2: Fix incorrect wording noticed by Jann Horn. > Remove deprecated and memfd_create discussion as suggested > by Florian Weimer. > > Since at least the 2.6 time frame, mremap would create a new mapping > of the same pages if

[patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-19 Thread Mike Kravetz
v2: Fix incorrect wording noticed by Jann Horn. Remove deprecated and memfd_create discussion as suggested by Florian Weimer. Since at least the 2.6 time frame, mremap would create a new mapping of the same pages if 'old_size == 0'. It would also leave the original mapping. This was

[patch v2] mremap.2: Add description of old_size == 0 functionality

2017-09-19 Thread Mike Kravetz
v2: Fix incorrect wording noticed by Jann Horn. Remove deprecated and memfd_create discussion as suggested by Florian Weimer. Since at least the 2.6 time frame, mremap would create a new mapping of the same pages if 'old_size == 0'. It would also leave the original mapping. This was