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From: Yuntao Wang <ytcoode@gmail.com>
To: linux-kernel@vger.kernel.org,
	x86@kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Baoquan He <bhe@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Simon Horman <horms@kernel.org>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Yuntao Wang <ytcoode@gmail.com>
Subject: [PATCH] x86/kexec: fix incorrect end address passed to kernel_ident_mapping_init()
Date: Thu, 21 Dec 2023 18:17:02 +0800
Message-ID: <20231221101702.20956-1-ytcoode@gmail.com>
Precedence: bulk
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kernel_ident_mapping_init() takes an exclusive memory range [pstart, pend)
where pend is not included in the range, while res represents an inclusive
memory range [start, end] where end is considered part of the range.

Therefore, passing res->end directly to kernel_ident_mapping_init() is
incorrect, the correct end address should be `res->end + 1`.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
---
 arch/x86/kernel/machine_kexec_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 6f8df998890e..bc0a5348b4a6 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -44,7 +44,7 @@ static int mem_region_callback(struct resource *res, void *arg)
 	struct init_pgtable_data *data = arg;
 
 	return kernel_ident_mapping_init(data->info, data->level4p,
-					 res->start, res->end);
+					 res->start, res->end + 1);
 }
 
 static int
-- 
2.43.0