Re: [Qemu-devel] [PATCH] sparc: Make sure we mmap at SHMLBA alignment

2017-12-15 Thread Peter Maydell
On 12 December 2017 at 05:53, Richard Henderson wrote: > On 12/08/2017 08:57 AM, Peter Maydell wrote: >> SPARC Linux has an oddity that it insists that mmap() >> of MAP_FIXED memory must be at an alignment defined by >> SHMLBA, which is more aligned than the page

Re: [Qemu-devel] [PATCH] sparc: Make sure we mmap at SHMLBA alignment

2017-12-11 Thread Richard Henderson
On 12/08/2017 08:57 AM, Peter Maydell wrote: > SPARC Linux has an oddity that it insists that mmap() > of MAP_FIXED memory must be at an alignment defined by > SHMLBA, which is more aligned than the page size > (typically, SHMLBA alignment is to 16K, and pages are 8K). > This is a relic of ancient

[Qemu-devel] [PATCH] sparc: Make sure we mmap at SHMLBA alignment

2017-12-08 Thread Peter Maydell
SPARC Linux has an oddity that it insists that mmap() of MAP_FIXED memory must be at an alignment defined by SHMLBA, which is more aligned than the page size (typically, SHMLBA alignment is to 16K, and pages are 8K). This is a relic of ancient hardware that had cache aliasing constraints, but even