This is a note to let you know that I've just added the patch titled
riscv: Don't use PGD entries for the linear mapping
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
riscv-don-t-use-pgd-entries-for-the-linear-mapping.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7439b31cb004e1055fdb3861a74e41823e4b075f
Author: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>
Date: Wed Nov 8 08:59:29 2023 +0100
riscv: Don't use PGD entries for the linear mapping
[ Upstream commit 629db01c64ff6cea08fc61b52426362689ef8618 ]
Propagating changes at this level is cumbersome as we need to go through
all the page tables when that happens (either when changing the
permissions or when splitting the mapping).
Note that this prevents the use of 4MB mapping for sv32 and 1GB mapping for
sv39 in the linear mapping.
Signed-off-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20231108075930.7157-2-alexghiti@xxxxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Stable-dep-of: c67ddf59ac44 ("riscv: force PAGE_SIZE linear mapping if debug_pagealloc is enabled")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 83ac1eb8e7e68..4d62f54698b99 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -668,16 +668,16 @@ void __init create_pgd_mapping(pgd_t *pgdp,
static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
phys_addr_t size)
{
- if (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
- return PGDIR_SIZE;
-
- if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
+ if (pgtable_l5_enabled &&
+ !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
return P4D_SIZE;
- if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
+ if (pgtable_l4_enabled &&
+ !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
return PUD_SIZE;
- if (!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
+ if (IS_ENABLED(CONFIG_64BIT) &&
+ !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
return PMD_SIZE;
return PAGE_SIZE;
