[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to h
From: |
Peter Xu |
Subject: |
Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory |
Date: |
Thu, 11 Mar 2021 16:37:56 -0500 |
On Mon, Mar 08, 2021 at 04:05:50PM +0100, David Hildenbrand wrote:
> We can create shared anonymous memory via
> "-object memory-backend-ram,share=on,..."
> which is, for example, required by PVRDMA for mremap() to work.
>
> Shared anonymous memory is weird, though. Instead of MADV_DONTNEED, we
> have to use MADV_REMOVE. MADV_DONTNEED fails silently and does nothing.
>
> Fixes: 06329ccecfa0 ("mem: add share parameter to memory-backend-ram")
I'm thinking whether we should keep this fixes - it's valid, however it could
unveil issues if those remapped ranges didn't get unmapped in time. After all
"not releasing some memory existed" seems not a huge deal for stable. No
strong opinion, just raise it up as a pure question.
> Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Peter Xu
- [PATCH v3 01/12] softmmu/physmem: Mark shared anonymous memory RAM_SHARED, (continued)
- [PATCH v3 01/12] softmmu/physmem: Mark shared anonymous memory RAM_SHARED, David Hildenbrand, 2021/03/08
- [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, David Hildenbrand, 2021/03/08
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, Dr. David Alan Gilbert, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, David Hildenbrand, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, Peter Xu, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, David Hildenbrand, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, David Hildenbrand, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, Peter Xu, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, David Hildenbrand, 2021/03/11
- Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory, Peter Xu, 2021/03/11
Re: [PATCH v3 02/12] softmmu/physmem: Fix ram_block_discard_range() to handle shared anonymous memory,
Peter Xu <=
[PATCH v3 03/12] softmmu/physmem: Fix qemu_ram_remap() to handle shared anonymous memory, David Hildenbrand, 2021/03/08
[PATCH v3 04/12] util/mmap-alloc: Factor out calculation of the pagesize for the guard page, David Hildenbrand, 2021/03/08
[PATCH v3 05/12] util/mmap-alloc: Factor out reserving of a memory region to mmap_reserve(), David Hildenbrand, 2021/03/08
[PATCH v3 06/12] util/mmap-alloc: Factor out activating of memory to mmap_activate(), David Hildenbrand, 2021/03/08
[PATCH v3 07/12] softmmu/memory: Pass ram_flags into qemu_ram_alloc_from_fd(), David Hildenbrand, 2021/03/08
[PATCH v3 08/12] softmmu/memory: Pass ram_flags into memory_region_init_ram_shared_nomigrate(), David Hildenbrand, 2021/03/08
[PATCH v3 09/12] util/mmap-alloc: Pass flags instead of separate bools to qemu_ram_mmap(), David Hildenbrand, 2021/03/08