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Message-Id: <0365f99ce2b9273e269a241394957cba924f995e.1551951985.git.christophe.leroy@c-s.fr>
From:   Christophe Leroy <christophe.leroy@c-s.fr>
Subject: [PATCH] powerpc/highmem: change BUG_ON() to WARN_ON()
To:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Michael Ellerman <mpe@ellerman.id.au>
Cc:     linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Date:   Thu,  7 Mar 2019 09:47:50 +0000 (UTC)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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@c-s.fr>
---
 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