[PATCH] x86/boot/compressed/64: Do not truncate gdt address
Before going to 32-bit trampoline we need to load GDT to make sure that we have the table with 32-bit code segment. The load was implemented incorrectly and the table address is truncated to 32-bit. It causes problems if gdt is above 4G. Reported-and-tested-by: Andrei VaginFixes: b4b56015ed1c ("x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G") Signed-off-by: Kirill A. Shutemov --- arch/x86/boot/compressed/head_64.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 70b30f2bc9e0..99a0e7993252 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -332,7 +332,7 @@ ENTRY(startup_64) /* Make sure we have GDT with 32-bit code segment */ leaqgdt(%rip), %rax - movl%eax, gdt64+2(%rip) + movq%rax, gdt64+2(%rip) lgdtgdt64(%rip) /* -- 2.15.1
[PATCH] x86/boot/compressed/64: Do not truncate gdt address
Before going to 32-bit trampoline we need to load GDT to make sure that we have the table with 32-bit code segment. The load was implemented incorrectly and the table address is truncated to 32-bit. It causes problems if gdt is above 4G. Reported-and-tested-by: Andrei Vagin Fixes: b4b56015ed1c ("x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G") Signed-off-by: Kirill A. Shutemov --- arch/x86/boot/compressed/head_64.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 70b30f2bc9e0..99a0e7993252 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -332,7 +332,7 @@ ENTRY(startup_64) /* Make sure we have GDT with 32-bit code segment */ leaqgdt(%rip), %rax - movl%eax, gdt64+2(%rip) + movq%rax, gdt64+2(%rip) lgdtgdt64(%rip) /* -- 2.15.1