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x86/boot/64: Use RIP_REL_REF() to access early_dynamic_pgts[]

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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: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-21-ardb+git@google.com
This commit is contained in:
Ard Biesheuvel
2024-02-21 12:35:10 +01:00
committed by Ingo Molnar
parent d9ec115805
commit b0fe5fb609
1 changed files with 5 additions and 6 deletions
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11
arch/x86/kernel/head64.c
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@@ -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;