6.6-stable review patch. If anyone has any objections, please let me know.
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From: Stephen Boyd sboyd@kernel.org
[ 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@kernel.org Cc: Frank Rowand frowand.list@gmail.com Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@redhat.com Cc: Borislav Petkov bp@alien8.de Cc: Dave Hansen dave.hansen@linux.intel.com Cc: x86@kernel.org Cc: H. Peter Anvin hpa@zytor.com Tested-by: Saurabh Sengar ssengar@linux.microsoft.com Signed-off-by: Stephen Boyd sboyd@kernel.org Link: https://lore.kernel.org/r/20240217010557.2381548-5-sboyd@kernel.org Signed-off-by: Rob Herring robh@kernel.org 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@kernel.org --- 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) { }