linux-kernel - [PATCH] x86/kaslr: simplify the code in mem_avoid

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Message-Id: <1566483962-10046-1-git-send-email-cai@lca.pw>
Date:   Thu, 22 Aug 2019 10:26:02 -0400
From:   Qian Cai <cai@....pw>
To:     tglx@...utronix.de, mingo@...hat.com, hpa@...or.com
Cc:     bhe@...hat.com, x86@...nel.org, linux-kernel@...r.kernel.org,
        Qian Cai <cai@....pw>
Subject: [PATCH] x86/kaslr: simplify the code in mem_avoid_memmap()

If "i >= MAX_MEMMAP_REGIONS" already when entering mem_avoid_memmap(),
even without the return statement the loop will not run anyway. The only
time it needs to set "memmap_too_large = true" in this situation is
"memmap_too_large" is "false" currently. Hence, the code could be
simplified.

Signed-off-by: Qian Cai <cai@....pw>
---
 arch/x86/boot/compressed/kaslr.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 2e53c056ba20..35c6942fb95b 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -176,9 +176,6 @@ static void mem_avoid_memmap(char *str)
 {
 	static int i;
 
-	if (i >= MAX_MEMMAP_REGIONS)
-		return;
-
 	while (str && (i < MAX_MEMMAP_REGIONS)) {
 		int rc;
 		unsigned long long start, size;
@@ -206,7 +203,7 @@ static void mem_avoid_memmap(char *str)
 	}
 
 	/* More than 4 memmaps, fail kaslr */
-	if ((i >= MAX_MEMMAP_REGIONS) && str)
+	if (i >= MAX_MEMMAP_REGIONS && !memmap_too_large)
 		memmap_too_large = true;
 }
 
-- 
1.8.3.1