| Message ID | 20210128105711.10428-1-rppt@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | x86/setup: consolidate early memory reservations | expand |
Hi, Any comments on this? On Thu, Jan 28, 2021 at 12:57:09PM +0200, Mike Rapoport wrote: > From: Mike Rapoport <rppt@linux.ibm.com> > > Hi, > > David noticed that we do some of memblock_reserve() calls after allocations > are possible: > > https://lore.kernel.org/lkml/6ba6bde3-1520-5cd0-f987-32d543f0b79f@redhat.com > > For now there is no actual problem because in top-down mode we allocate > from the end of the memory and in bottom-up mode we allocate above the > kernel image. But there is a patch in the mm tree that allow bottom-up > allocations below the kernel: > > https://lore.kernel.org/lkml/20201217201214.3414100-2-guro@fb.com > > and with this change we may get a memory corruption if an allocation steps > on some of the firmware areas that are yet to be reserved. > > The below patches consolidate early memory reservations done during > setup_arch() so that memory used by firmware, bootloader, kernel text/data > and the memory that should be excluded from the available memory for > whatever other reason is reserved before memblock allocations are possible. > > The patches are vs v5.11-rc3-mmots-2021-01-12-02-00 as I think they are > prerequisite for the memblock bottom-up changes, but if needed I can rebase > then on another tree. > > v2: > * get rid of trim_platform_memory_ranges() and call trim_snb_memory() > directly, per Boris comments > * massage changelog and comments to use passive voice, per Boris > * add Acked-by and Reviewed-by, thanks Boris and David > > v1: https://lore.kernel.org/lkml/20210115083255.12744-1-rppt@kernel.org > > Mike Rapoport (2): > x86/setup: consolidate early memory reservations > x86/setup: merge several reservations of start of the memory > > arch/x86/kernel/setup.c | 96 ++++++++++++++++++----------------------- > 1 file changed, 42 insertions(+), 54 deletions(-) > > -- > 2.28.0 >
From: Mike Rapoport <rppt@linux.ibm.com> Hi, David noticed that we do some of memblock_reserve() calls after allocations are possible: https://lore.kernel.org/lkml/6ba6bde3-1520-5cd0-f987-32d543f0b79f@redhat.com For now there is no actual problem because in top-down mode we allocate from the end of the memory and in bottom-up mode we allocate above the kernel image. But there is a patch in the mm tree that allow bottom-up allocations below the kernel: https://lore.kernel.org/lkml/20201217201214.3414100-2-guro@fb.com and with this change we may get a memory corruption if an allocation steps on some of the firmware areas that are yet to be reserved. The below patches consolidate early memory reservations done during setup_arch() so that memory used by firmware, bootloader, kernel text/data and the memory that should be excluded from the available memory for whatever other reason is reserved before memblock allocations are possible. The patches are vs v5.11-rc3-mmots-2021-01-12-02-00 as I think they are prerequisite for the memblock bottom-up changes, but if needed I can rebase then on another tree. v2: * get rid of trim_platform_memory_ranges() and call trim_snb_memory() directly, per Boris comments * massage changelog and comments to use passive voice, per Boris * add Acked-by and Reviewed-by, thanks Boris and David v1: https://lore.kernel.org/lkml/20210115083255.12744-1-rppt@kernel.org Mike Rapoport (2): x86/setup: consolidate early memory reservations x86/setup: merge several reservations of start of the memory arch/x86/kernel/setup.c | 96 ++++++++++++++++++----------------------- 1 file changed, 42 insertions(+), 54 deletions(-)