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From:   Abhinav Singh <singhabhinav9051571833@gmail.com>
To:     kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org,
        decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com
Cc:     linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kernel-mentees@lists.linuxfoundation.org,
        Abhinav Singh <singhabhinav9051571833@gmail.com>
Subject: [PATCH] Fixing warning cast removes address space '__iomem' of expression
Date:   Tue, 24 Oct 2023 16:58:32 +0530
Message-Id: <20231024112832.737832-1-singhabhinav9051571833@gmail.com>
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This patch fixes sparse complaining about the removal of __iomem address
space when casting the return value of this function ioremap_cache(...)
from `void __ioremap*` to `void*`.

I think there are two way of fixing it, first one is changing the
datatype of variable `ghcb_va` from `void*` to `void __iomem*` . 
Second way of fixing it is using the memremap(...) which is 
done in this patch.

Signed-off-by: Abhinav Singh <singhabhinav9051571833@gmail.com>
---
 arch/x86/hyperv/hv_init.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 21556ad87f4b..c14161add274 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -70,7 +70,7 @@ static int hyperv_init_ghcb(void)
 
 	/* Mask out vTOM bit. ioremap_cache() maps decrypted */
 	ghcb_gpa &= ~ms_hyperv.shared_gpa_boundary;
-	ghcb_va = (void *)ioremap_cache(ghcb_gpa, HV_HYP_PAGE_SIZE);
+	ghcb_va = memremap(ghcb_gpa, HV_HYP_PAGE_SIZE, MEMREMAP_WB);
 	if (!ghcb_va)
 		return -ENOMEM;
 
-- 
2.39.2