[PATCH] Revert "swiotlb: panic if nslabs is too small"

From: Yu Zhao
Date: Mon Aug 29 2022 - 19:29:43 EST


This reverts commit 0bf28fc40d89b1a3e00d1b79473bad4e9ca20ad1.

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

[1]: https://lore.kernel.org/r/CAHk-=wit-DmhMfQErY29JSPjFgebx_Ld+pnerc4J2Ag990WwAA@xxxxxxxxxxxxxx/
[2]: https://lore.kernel.org/r/20220820012031.1285979-1-yuzhao@xxxxxxxxxx/

Fixes: 0bf28fc40d89b ("swiotlb: panic if nslabs is too small")
Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx>
---
kernel/dma/swiotlb.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index c5a9190b218f..b3ede72eba5d 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -325,10 +325,6 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
if (!default_nareas)
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 +337,7 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
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;
}


base-commit: c40e8341e3b3bb27e3a65b06b5b454626234c4f0
--
2.37.2.672.g94769d06f0-goog