On Wed, 11 May 2022, Christoph Hellwig wrote:
> For historical reasons the switlb code paniced when the metadata could
> not be allocated, but just printed a warning when the actual main
> swiotlb buffer could not be allocated. Restore this somewhat unexpected
> behavior as changing it caused a boot failure on the Microchip RISC-V
> PolarFire SoC Icicle kit.
>
> Fixes: 6424e31b1c05 ("swiotlb: remove swiotlb_init_with_tbl and
> swiotlb_init_late_with_tbl")
> Reported-by: Conor Dooley <[email protected]>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Tested-by: Conor Dooley <[email protected]>
Reviewed-by: Stefano Stabellini <[email protected]>
> ---
> kernel/dma/swiotlb.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
> index e2ef0864eb1e5..3e992a308c8a1 100644
> --- a/kernel/dma/swiotlb.c
> +++ b/kernel/dma/swiotlb.c
> @@ -254,8 +254,10 @@ void __init swiotlb_init_remap(bool addressing_limit,
> unsigned int flags,
> tlb = memblock_alloc(bytes, PAGE_SIZE);
> else
> tlb = memblock_alloc_low(bytes, PAGE_SIZE);
> - if (!tlb)
> - panic("%s: failed to allocate tlb structure\n", __func__);
> + if (!tlb) {
> + pr_warn("%s: failed to allocate tlb structure\n", __func__);
> + return;
> + }
>
> if (remap && remap(tlb, nslabs) < 0) {
> memblock_free(tlb, PAGE_ALIGN(bytes));
> --
> 2.30.2
>
