[PATCH] powerpc/highmem: change BUG_ON() to WARN_ON()

From: Christophe Leroy
Date: Thu Mar 07 2019 - 04:47:55 EST


In arch/powerpc/mm/highmem.c, BUG_ON() is called only when
CONFIG_DEBUG_HIGHMEM is selected, this means the BUG_ON() is
not vital and can be replaced by a a WARN_ON

At the sametime, use IS_ENABLED() instead of #ifdef to clean a bit.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/mm/highmem.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index 82a0e37557a5..b68c9f20fbdf 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c
@@ -43,9 +43,7 @@ void *kmap_atomic_prot(struct page *page, pgprot_t prot)
type = kmap_atomic_idx_push();
idx = type + KM_TYPE_NR*smp_processor_id();
vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte-idx)));
-#endif
+ WARN_ON(IS_ENABLED(CONFIG_DEBUG_HIGHMEM) && !pte_none(*(kmap_pte - idx)));
__set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot), 1);
local_flush_tlb_page(NULL, vaddr);

@@ -56,7 +54,7 @@ EXPORT_SYMBOL(kmap_atomic_prot);
void __kunmap_atomic(void *kvaddr)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int type __maybe_unused;
+ int type;

if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
pagefault_enable();
@@ -66,12 +64,11 @@ void __kunmap_atomic(void *kvaddr)

type = kmap_atomic_idx();

-#ifdef CONFIG_DEBUG_HIGHMEM
- {
+ if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) {
unsigned int idx;

idx = type + KM_TYPE_NR * smp_processor_id();
- BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+ WARN_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));

/*
* force other mappings to Oops if they'll try to access
@@ -80,7 +77,6 @@ void __kunmap_atomic(void *kvaddr)
pte_clear(&init_mm, vaddr, kmap_pte-idx);
local_flush_tlb_page(NULL, vaddr);
}
-#endif

kmap_atomic_idx_pop();
pagefault_enable();
--
2.13.3