From: Maciej W. Rozycki <macro@orcam.me.uk>
Date: Mon, 26 Aug 2024 09:21:47 +0000 (+0100)
Subject: x86/EISA: Dereference memory directly instead of using readl()
X-Git-Tag: v6.12~458^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a678164aadbf68d80f7ab79b8bd5cfe3711e42fa;p=platform%2Fkernel%2Flinux-amlogic.git

x86/EISA: Dereference memory directly instead of using readl()

Sparse expect an __iomem pointer, but after converting the EISA probe to
memremap() the pointer is a regular memory pointer. Access it directly
instead.

[ tglx: Converted it to fix the already applied version  ]

Fixes: 80a4da05642c ("x86/EISA: Use memremap() to probe for the EISA BIOS signature")
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/alpine.DEB.2.21.2408261015270.30766@angie.orcam.me.uk
---

diff --git a/arch/x86/kernel/eisa.c b/arch/x86/kernel/eisa.c
index 5a4f99a098bf..9535a6507db7 100644
--- a/arch/x86/kernel/eisa.c
+++ b/arch/x86/kernel/eisa.c
@@ -11,13 +11,13 @@
 
 static __init int eisa_bus_probe(void)
 {
-	void *p;
+	u32 *p;
 
 	if ((xen_pv_domain() && !xen_initial_domain()) || cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
 		return 0;
 
 	p = memremap(0x0FFFD9, 4, MEMREMAP_WB);
-	if (p && readl(p) == 'E' + ('I' << 8) + ('S' << 16) + ('A' << 24))
+	if (p && *p == 'E' + ('I' << 8) + ('S' << 16) + ('A' << 24))
 		EISA_bus = 1;
 	memunmap(p);
 	return 0;