Re: Bug 205201 - Booting halts if Dawicontrol DC-2976 UW SCSI board installed, unless RAM size limited to 3500M

[Christian Zigotzky]

On 27 November 2019 at 07:56 am, Mike Rapoport wrote:

Maybe we'll simply force bottom up allocation before calling
swiotlb_init()? Anyway, it's the last memblock allocation.


diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 62f74b1b33bd..771e6cf7e2b9 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -286,14 +286,15 @@ void __init mem_init(void)
        /*
         * book3s is limited to 16 page sizes due to encoding this in
         * a 4-bit field for slices.
         */
        BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
  
  #ifdef CONFIG_SWIOTLB
+       memblock_set_bottom_up(true);
        swiotlb_init(0);
  #endif
  
  	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
        set_max_mapnr(max_pfn);
        memblock_free_all();
  
  
Hello Mike,

I tested the latest Git kernel with your new patch today. My PCI TV card 
works without any problems.

Thanks,
Christian