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From:   Huacai Chen <chenhuacai@loongson.cn>
To:     Arnd Bergmann <arnd@arndb.de>, Huacai Chen <chenhuacai@kernel.org>
Cc:     loongarch@lists.linux.dev, linux-arch@vger.kernel.org,
        Xuefeng Li <lixuefeng@loongson.cn>,
        Guo Ren <guoren@kernel.org>, Xuerui Wang <kernel@xen0n.name>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>,
        linux-kernel@vger.kernel.org, loongson-kernel@lists.loongnix.cn,
        Huacai Chen <chenhuacai@loongson.cn>
Subject: [PATCH] LoongArch: Silence the boot warning about 'nokaslr'
Date:   Wed, 15 Nov 2023 22:15:30 +0800
Message-Id: <20231115141530.2534778-1-chenhuacai@loongson.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
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The kernel parameter 'nokaslr' is handled before start_kernel(), so we
don't need early_param() to mark it technically. But it can cause a boot
warning as follows:

Unknown kernel command line parameters "nokaslr", will be passed to user space.

When we use 'init=/bin/bash', 'nokaslr' which passed to user space will
even cause a kernel panic. So we use early_param() to mark 'nokaslr',
simply print a notice and silence the boot warning (also fix a potential
panic). This logic is similar to RISC-V.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
 arch/loongarch/kernel/relocate.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/loongarch/kernel/relocate.c b/arch/loongarch/kernel/relocate.c
index 6c3eff9af9fb..c2f5c2bdeb7f 100644
--- a/arch/loongarch/kernel/relocate.c
+++ b/arch/loongarch/kernel/relocate.c
@@ -102,6 +102,14 @@ static inline __init unsigned long get_random_boot(void)
 	return hash;
 }
 
+static int __init nokaslr(char *p)
+{
+	pr_info("KASLR is disabled.\n");
+
+	return 0; /* Print a notice and silence the boot warning */
+}
+early_param("nokaslr", nokaslr);
+
 static inline __init bool kaslr_disabled(void)
 {
 	char *str;
-- 
2.39.3