6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stephen Boyd <sboyd@xxxxxxxxxx> [ Upstream commit 40f18dbbb42c56019b889b5b1fdce3da89e354da ] Call this function unconditionally so that we can populate an empty DTB on platforms that don't boot with a firmware provided or builtin DTB. There's no harm in calling unflatten_device_tree() unconditionally here. If there isn't a non-NULL 'initial_boot_params' pointer then unflatten_device_tree() returns early. Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Frank Rowand <frowand.list@xxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: x86@xxxxxxxxxx Cc: H. Peter Anvin <hpa@xxxxxxxxx> Tested-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240217010557.2381548-5-sboyd@xxxxxxxxxx Signed-off-by: Rob Herring <robh@xxxxxxxxxx> Stable-dep-of: b2473a359763 ("of/fdt: add dt_phys arg to early_init_dt_scan and early_init_dt_verify") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/kernel/devicetree.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c index c13c9cb40b9b4..47fe7de1575dd 100644 --- a/arch/x86/kernel/devicetree.c +++ b/arch/x86/kernel/devicetree.c @@ -283,22 +283,24 @@ static void __init x86_flattree_get_config(void) u32 size, map_len; void *dt; - if (!initial_dtb) - return; - - map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128); + if (initial_dtb) { + map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128); + + dt = early_memremap(initial_dtb, map_len); + size = fdt_totalsize(dt); + if (map_len < size) { + early_memunmap(dt, map_len); + dt = early_memremap(initial_dtb, size); + map_len = size; + } - dt = early_memremap(initial_dtb, map_len); - size = fdt_totalsize(dt); - if (map_len < size) { - early_memunmap(dt, map_len); - dt = early_memremap(initial_dtb, size); - map_len = size; + early_init_dt_verify(dt); } - early_init_dt_verify(dt); unflatten_and_copy_device_tree(); - early_memunmap(dt, map_len); + + if (initial_dtb) + early_memunmap(dt, map_len); } #else static inline void x86_flattree_get_config(void) { } -- 2.43.0
