On 2021-03-02 12:59, Sasha Levin wrote:
From: Andreas Larsson <andreas@xxxxxxxxxxx>
[ Upstream commit bda166930c37604ffa93f2425426af6921ec575a ]
Commit cca079ef8ac29a7c02192d2bad2ffe4c0c5ffdd0 changed sparc32 to use
memblocks instead of bootmem, but also made high memory available via
memblock allocation which does not work together with e.g. phys_to_virt
and can lead to kernel panic.
This changes back to only low memory being allocatable in the early
stages, now using memblock allocation.
Signed-off-by: Andreas Larsson <andreas@xxxxxxxxxxx>
Acked-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/sparc/mm/init_32.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index 3b7092d9ea8f..4abe4bf08377 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -240,6 +240,9 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
+ /* Only allow low memory to be allocated via memblock allocation */
+ memblock_set_current_limit(max_low_pfn << PAGE_SHIFT);
+
return max_pfn;
}
This is not needed for 4.4, and will not compile, as the problem it
fixes was introduced in 4.19.
--
Andreas Larsson
