Commit b0fe5fb6 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_dynamic_pgts[] 



early_dynamic_pgts[] and next_early_pgt are accessed from code that
executes from a 1:1 mapping so it cannot use a plain access 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/20240221113506.2565718-21-ardb+git@google.com
parent d9ec1158

arch/x86/kernel/head64.c

+5 −6
Original line number Diff line number Diff line
@@ -170,6 +170,7 @@ static unsigned long __head sme_postprocess_startup(struct boot_params *bp, pmdv 
unsigned long __head __startup_64(unsigned long physaddr,

				  struct boot_params *bp)

{

	pmd_t (*early_pgts)[PTRS_PER_PMD] = RIP_REL_REF(early_dynamic_pgts);

	unsigned long load_delta, *p;

	unsigned long pgtable_flags;

	pgdval_t *pgd;
@@ -179,7 +180,6 @@ unsigned long __head __startup_64(unsigned long physaddr, 
	pteval_t *mask_ptr;

	bool la57;

	int i;

	unsigned int *next_pgt_ptr;



	la57 = check_la57_support(physaddr);
@@ -231,15 +231,14 @@ unsigned long __head __startup_64(unsigned long physaddr, 
	 * it avoids problems around wraparound.

	 */



	next_pgt_ptr = fixup_pointer(&next_early_pgt, physaddr);

	pud = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], physaddr);

	pmd = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], physaddr);

	pud = &early_pgts[0]->pmd;

	pmd = &early_pgts[1]->pmd;

	RIP_REL_REF(next_early_pgt) = 2;



	pgtable_flags = _KERNPG_TABLE_NOENC + sme_get_me_mask();



	if (la57) {

		p4d = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++],

				    physaddr);

		p4d = &early_pgts[RIP_REL_REF(next_early_pgt)++]->pmd;



		i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD;

		pgd[i + 0] = (pgdval_t)p4d + pgtable_flags;