From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Lucas Tanure Date: Wed, 12 Apr 2023 18:46:20 -0400 Subject: FROMLIST(v4): of: fdt: Scan /memreserve/ last Change the scanning /memreserve/ and /reserved-memory node order to fix Kernel panic on Khadas Vim3 Board. If /memreserve/ goes first, the memory is reserved, but nomap can't be applied to the region. So the memory won't be used by Linux, but it is still present in the linear map as normal memory, which allows speculation. Legitimate access to adjacent pages will cause the CPU to end up prefetching into them leading to Kernel panic. So /reserved-memory node should go first, as it has a more updated description of the memory regions and can apply flags, like nomap. Signed-off-by: Lucas Tanure --- drivers/of/fdt.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 81508e8b34d2..0252a7189d99 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -626,6 +626,9 @@ void __init early_init_fdt_scan_reserved_mem(void) if (!initial_boot_params) return; + fdt_scan_reserved_mem(); + fdt_reserve_elfcorehdr(); + /* Process header /memreserve/ fields */ for (n = 0; ; n++) { fdt_get_mem_rsv(initial_boot_params, n, &base, &size); @@ -634,8 +637,6 @@ void __init early_init_fdt_scan_reserved_mem(void) memblock_reserve(base, size); } - fdt_scan_reserved_mem(); - fdt_reserve_elfcorehdr(); fdt_init_reserved_mem(); } -- Armbian