From: Andreas Rammhold andreas@rammhold.de
commit 2a12187d5853d9fd5102278cecef7dac7c8ce7ea upstream.
If memory has been found early_init_dt_scan_memory now returns 1. If it hasn't found any memory it will return 0, allowing other memory setup mechanisms to carry on.
Previously early_init_dt_scan_memory always returned 0 without distinguishing between any kind of memory setup being done or not. Any code path after the early_init_dt_scan memory call in the ramips plat_mem_setup code wouldn't be executed anymore. Making early_init_dt_scan_memory the only way to initialize the memory.
Some boards, including my mt7621 based Cudy X6 board, depend on memory initialization being done via the soc_info.mem_detect function pointer. Those wouldn't be able to obtain memory and panic the kernel during early bootup with the message "early_init_dt_alloc_memory_arch: Failed to allocate 12416 bytes align=0x40".
Fixes: 1f012283e936 ("of/fdt: Rework early_init_dt_scan_memory() to call directly") Cc: stable@vger.kernel.org Signed-off-by: Andreas Rammhold andreas@rammhold.de Link: https://lore.kernel.org/r/20221223112748.2935235-1-andreas@rammhold.de Signed-off-by: Rob Herring robh@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/mips/ralink/of.c | 2 +- drivers/of/fdt.c | 6 ++++-- 2 files changed, 5 insertions(+), 3 deletions(-)
--- a/arch/mips/ralink/of.c +++ b/arch/mips/ralink/of.c @@ -64,7 +64,7 @@ void __init plat_mem_setup(void) dtb = get_fdt(); __dt_setup_arch(dtb);
- if (!early_init_dt_scan_memory()) + if (early_init_dt_scan_memory()) return;
if (soc_info.mem_detect) --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -1099,7 +1099,7 @@ u64 __init dt_mem_next_cell(int s, const */ int __init early_init_dt_scan_memory(void) { - int node; + int node, found_memory = 0; const void *fdt = initial_boot_params;
fdt_for_each_subnode(node, fdt, 0) { @@ -1139,6 +1139,8 @@ int __init early_init_dt_scan_memory(voi
early_init_dt_add_memory_arch(base, size);
+ found_memory = 1; + if (!hotpluggable) continue;
@@ -1147,7 +1149,7 @@ int __init early_init_dt_scan_memory(voi base, base + size); } } - return 0; + return found_memory; }
int __init early_init_dt_scan_chosen(char *cmdline)