Commit eb54c2ae authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Ingo Molnar
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x86/boot/64: Use RIP_REL_REF() to access early page tables 



The early statically allocated page tables are populated from code that
executes from a 1:1 mapping so it cannot use plain accesses from C.
Replace the use of fixup_pointer() with RIP_REL_REF(), which is better
and simpler.

Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-23-ardb+git@google.com
parent 4f8b6cf2

arch/x86/kernel/head64.c

+4 −6
Original line number Diff line number Diff line
@@ -215,13 +215,11 @@ unsigned long __head __startup_64(unsigned long physaddr, 
		p4d[511] += load_delta;

	}



	pud = fixup_pointer(level3_kernel_pgt, physaddr);

	pud[510] += load_delta;

	pud[511] += load_delta;

	RIP_REL_REF(level3_kernel_pgt)[PTRS_PER_PUD - 2].pud += load_delta;

	RIP_REL_REF(level3_kernel_pgt)[PTRS_PER_PUD - 1].pud += load_delta;



	pmd = fixup_pointer(level2_fixmap_pgt, physaddr);

	for (i = FIXMAP_PMD_TOP; i > FIXMAP_PMD_TOP - FIXMAP_PMD_NUM; i--)

		pmd[i] += load_delta;

		RIP_REL_REF(level2_fixmap_pgt)[i].pmd += load_delta;



	/*

	 * Set up the identity mapping for the switchover.  These
@@ -284,7 +282,7 @@ unsigned long __head __startup_64(unsigned long physaddr, 
	 * error, causing the BIOS to halt the system.

	 */



	pmd = fixup_pointer(level2_kernel_pgt, physaddr);

	pmd = &RIP_REL_REF(level2_kernel_pgt)->pmd;



	/* invalidate pages before the kernel image */

	for (i = 0; i < pmd_index((unsigned long)_text); i++)