The vmalloc_fault() path was removed and to avoid syncing the vmalloc PGD
mappings, they are now preallocated. But if the kernel can use a PUD
mapping (which in sv39 is actually a PGD mapping) for large vmalloc
allocation, it will free the current unused preallocated PGD mapping and
install a new leaf one. Since there is no sync anymore, some page tables
lack this new mapping and that triggers a panic.
So only allow PUD mappings for sv48 and sv57.
Fixes: 7d3332be01 ("riscv: mm: Pre-allocate PGD entries for vmalloc/modules area")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20230808130709.1502614-1-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
In the x86 MM code we'd like to untangle various types of historic
header dependency spaghetti, but for this we'd need to pass to
the generic vmalloc code various vmalloc related defines that
customarily come via the <asm/page.h> low level arch header.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
