Revert "swiotlb: panic if nslabs is too small"

This reverts commit 0bf28fc40d89b1a3e00d1b79473bad4e9ca20ad1.

Reasons:
  1. new panic()s shouldn't be added [1].
  2. It does no "cleanup" but breaks MIPS [2].

v2: properly solved the conflict [3] with
commit 20347fca71a38 ("swiotlb: split up the global swiotlb lock")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
[1] https://lore.kernel.org/r/CAHk-=wit-DmhMfQErY29JSPjFgebx_Ld+pnerc4J2Ag990WwAA@mail.gmail.com/
[2] https://lore.kernel.org/r/20220820012031.1285979-1-yuzhao@google.com/
[3] https://lore.kernel.org/r/202208310701.LKr1WDCh-lkp@intel.com/

Fixes: 0bf28fc40d89b ("swiotlb: panic if nslabs is too small")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index c5a9190..dd88639 100644 (file)
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -326,9 +326,6 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
                swiotlb_adjust_nareas(num_possible_cpus());
 
        nslabs = default_nslabs;
-       if (nslabs < IO_TLB_MIN_SLABS)
-               panic("%s: nslabs = %lu too small\n", __func__, nslabs);
-
        /*
         * By default allocate the bounce buffer memory from low memory, but
         * allow to pick a location everywhere for hypervisors with guest
@@ -341,8 +338,7 @@ retry:
        else
                tlb = memblock_alloc_low(bytes, PAGE_SIZE);
        if (!tlb) {
-               pr_warn("%s: Failed to allocate %zu bytes tlb structure\n",
-                       __func__, bytes);
+               pr_warn("%s: failed to allocate tlb structure\n", __func__);
                return;
        }