arch/riscv/mm/init.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
Move the dma_contiguous_reserve() call from setup_bootmem() to
misc_mem_init(), placing it after arch_numa_init(). This ensures that
NUMA topology is initialized when reserving contiguous memory for DMA.
Tested with CMA_SIZE_PERNUMA enabled and two NUMA nodes on QEMU:
qemu-system-riscv64 \
-machine virt \
-nographic \
-smp 2 -m 512M \
-numa node,nodeid=0,cpus=0,memdev=m0 \
-numa node,nodeid=1,cpus=1,memdev=m1 \
-object memory-backend-ram,id=m0,size=256M \
-object memory-backend-ram,id=m1,size=256M \
-kernel arch/riscv/boot/Image \
-append "console=ttyS0 earlycon loglevel=7 cma=16M"
Unpatched kernel's log (one global CMA pool and no per-nodepools, 16 MiB
cma-reserved):
[ 0.000000] cma: Reserved 16 MiB at 0x000000009ee00000
...
[ 0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x000000008fffffff]
[ 0.000000] Initmem setup node 1 [mem 0x0000000090000000-0x000000009fffffff]
...
[ 0.056397] smp: Brought up 2 nodes, 2 CPUs
[ 0.066135] Memory: 449288K/524288K available (12279K kernel code, 5980K rwdata, 6144K rodata, 2467K init, 482K bss, 54504K reserved, 16384K cma-reserved)
Patched kernel's log (three CMA pools are created, 48 MiB total),
[ 0.000000] cma: Reserved 16 MiB at 0x000000009ee00000
[ 0.000000] cma: Reserved 16 MiB at 0x000000008ee00000
[ 0.000000] cma: Reserved 16 MiB at 0x000000009de00000
...
[ 0.054251] smp: Brought up 2 nodes, 2 CPUs
[ 0.064082] Memory: 416520K/524288K available (12279K kernel code, 5980K rwdata, 6144K rodata, 2467K init, 482K bss, 54504K reserved, 49152K cma-reserved)
Signed-off-by: Eder Zulian <ezulian@redhat.com>
---
arch/riscv/mm/init.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 85bdcce63a3e..79a658ebe74d 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -295,8 +295,6 @@ static void __init setup_bootmem(void)
*/
if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
-
- dma_contiguous_reserve(dma32_phys_limit);
}
#ifdef CONFIG_RELOCATABLE
@@ -1349,6 +1347,7 @@ void __init misc_mem_init(void)
{
early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
arch_numa_init();
+ dma_contiguous_reserve(dma32_phys_limit);
#ifdef CONFIG_SPARSEMEM_VMEMMAP
/* The entire VMEMMAP region has been populated. Flush TLB for this region */
local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END);
--
2.55.0Hi, On Tue, 14 Jul 2026, Eder Zulian wrote: > Move the dma_contiguous_reserve() call from setup_bootmem() to > misc_mem_init(), placing it after arch_numa_init(). This ensures that > NUMA topology is initialized when reserving contiguous memory for DMA. > > Tested with CMA_SIZE_PERNUMA enabled and two NUMA nodes on QEMU: > > qemu-system-riscv64 \ > -machine virt \ > -nographic \ > -smp 2 -m 512M \ > -numa node,nodeid=0,cpus=0,memdev=m0 \ > -numa node,nodeid=1,cpus=1,memdev=m1 \ > -object memory-backend-ram,id=m0,size=256M \ > -object memory-backend-ram,id=m1,size=256M \ > -kernel arch/riscv/boot/Image \ > -append "console=ttyS0 earlycon loglevel=7 cma=16M" > > Unpatched kernel's log (one global CMA pool and no per-nodepools, 16 MiB > cma-reserved): > > [ 0.000000] cma: Reserved 16 MiB at 0x000000009ee00000 > ... > [ 0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x000000008fffffff] > [ 0.000000] Initmem setup node 1 [mem 0x0000000090000000-0x000000009fffffff] > ... > [ 0.056397] smp: Brought up 2 nodes, 2 CPUs > [ 0.066135] Memory: 449288K/524288K available (12279K kernel code, 5980K rwdata, 6144K rodata, 2467K init, 482K bss, 54504K reserved, 16384K cma-reserved) > > Patched kernel's log (three CMA pools are created, 48 MiB total), > > [ 0.000000] cma: Reserved 16 MiB at 0x000000009ee00000 > [ 0.000000] cma: Reserved 16 MiB at 0x000000008ee00000 > [ 0.000000] cma: Reserved 16 MiB at 0x000000009de00000 > ... > [ 0.054251] smp: Brought up 2 nodes, 2 CPUs > [ 0.064082] Memory: 416520K/524288K available (12279K kernel code, 5980K rwdata, 6144K rodata, 2467K init, 482K bss, 54504K reserved, 49152K cma-reserved) > > Signed-off-by: Eder Zulian <ezulian@redhat.com> Thanks, queued for v7.3. - Paul
© 2016 - 2026 Red Hat, Inc.