On 1/31/2024 7:27 AM, Rob Herring wrote: > On Fri, Jan 26, 2024 at 03:53:46PM -0800, Oreoluwa Babatunde wrote: >> Call early_fdt_scan_reserved_mem() in place of >> early_init_fdt_scan_reserved_mem() to carry out the first stage of the >> reserved memory processing only. >> >> The early_fdt_scan_reserved_mem() function is used to scan through the >> DT and mark all the reserved memory regions as reserved or nomap as >> needed, as well as allocate the memory required by the >> dynamically-placed >> reserved memory regions. >> >> The second stage of the reserved memory processing is done by >> fdt_init_reserved_mem(). This function is used to store the information >> of the statically-placed reserved memory nodes in the reserved_mem >> array as well as call the region specific initialization function on all >> the stored reserved memory regions. >> >> The call to fdt_init_reserved_mem() is placed right after >> early_fdt_scan_reserved_mem() since memblock allocated memory should >> already be writable at this point. >> >> Signed-off-by: Oreoluwa Babatunde <quic_obabatun@xxxxxxxxxxx> >> --- >> arch/loongarch/kernel/setup.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c >> index edf2bba80130..72b164d3ace0 100644 >> --- a/arch/loongarch/kernel/setup.c >> +++ b/arch/loongarch/kernel/setup.c >> @@ -30,6 +30,7 @@ >> #include <linux/dma-map-ops.h> >> #include <linux/libfdt.h> >> #include <linux/of_fdt.h> >> +#include <linux/of_reserved_mem.h> >> #include <linux/of_address.h> >> #include <linux/suspend.h> >> #include <linux/swiotlb.h> >> @@ -390,8 +391,9 @@ static void __init arch_mem_init(char **cmdline_p) >> >> check_kernel_sections_mem(); >> >> - early_init_fdt_scan_reserved_mem(); >> + early_fdt_scan_reserved_mem(); > Looking at the loongarch code, there's an existing problem with the > order of init. This is done after unflattening and copying the DT. That > means the kernel could freely allocate memory for the DT in a reserved > region. > > Rob Same here, I think we should be able to move the call to early_init_fdt_scan_reserved_mem() higher in the init sequence without having any issues. Will try this out and see. Regards, Oreoluwa
