[PATCH v3 40/60] arm64: Revert "mm: provide idmap pointer to cpu_replace_ttbr1()"

Ard Biesheuvel
2023-03-07T14:12:27Z

This reverts commit 1682c45b920643c, which is no longer needed now that
we create the permanent kernel mapping directly during early boot.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/arm64/include/asm/mmu_context.h | 13 ++++---------
arch/arm64/kernel/cpufeature.c | 2 +-
arch/arm64/kernel/suspend.c | 2 +-
arch/arm64/mm/kasan_init.c | 4 ++--
4 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h
index f9ae2891e4c72c7f..bc1cef5002d60e02 100644
--- a/arch/arm64/include/asm/mmu_context.h
+++ b/arch/arm64/include/asm/mmu_context.h
@@ -104,18 +104,13 @@ static inline void cpu_uninstall_idmap(void)
cpu_switch_mm(mm->pgd, mm);
}

-static inline void __cpu_install_idmap(pgd_t *idmap)
+static inline void cpu_install_idmap(void)
{
cpu_set_reserved_ttbr0();
local_flush_tlb_all();
cpu_set_idmap_tcr_t0sz();

- cpu_switch_mm(lm_alias(idmap), &init_mm);
-}
-
-static inline void cpu_install_idmap(void)
-{
- __cpu_install_idmap(idmap_pg_dir);
+ cpu_switch_mm(lm_alias(idmap_pg_dir), &init_mm);
}

/*
@@ -146,7 +141,7 @@ static inline void cpu_install_ttbr0(phys_addr_t ttbr0, unsigned long t0sz)
* Atomically replaces the active TTBR1_EL1 PGD with a new VA-compatible PGD,
* avoiding the possibility of conflicting TLB entries being allocated.
*/
-static inline void cpu_replace_ttbr1(pgd_t *pgdp, pgd_t *idmap)
+static inline void cpu_replace_ttbr1(pgd_t *pgdp)
{
typedef void (ttbr_replace_func)(phys_addr_t);
extern ttbr_replace_func idmap_cpu_replace_ttbr1;
@@ -170,7 +165,7 @@ static inline void cpu_replace_ttbr1(pgd_t *pgdp, pgd_t *idmap)

replace_phys = (void *)__pa_symbol(idmap_cpu_replace_ttbr1);

- __cpu_install_idmap(idmap);
+ cpu_install_idmap();

/*
* We really don't want to take *any* exceptions while TTBR1 is
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index e9788671be044a47..b206de4758ce6fb3 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -3456,7 +3456,7 @@ subsys_initcall_sync(init_32bit_el0_mask);

static void __maybe_unused cpu_enable_cnp(struct arm64_cpu_capabilities const *cap)
{
- cpu_replace_ttbr1(lm_alias(swapper_pg_dir), idmap_pg_dir);
+ cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
}

/*
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c
index 0fbdf5fe64d8da08..7c2391851db6c198 100644
--- a/arch/arm64/kernel/suspend.c
+++ b/arch/arm64/kernel/suspend.c
@@ -55,7 +55,7 @@ void notrace __cpu_suspend_exit(void)

/* Restore CnP bit in TTBR1_EL1 */
if (system_supports_cnp())
- cpu_replace_ttbr1(lm_alias(swapper_pg_dir), idmap_pg_dir);
+ cpu_replace_ttbr1(lm_alias(swapper_pg_dir));

/*
* PSTATE was not saved over suspend/resume, re-enable any detected
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index df98f496539f0e39..7e32f21fb8e1e227 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -221,7 +221,7 @@ static void __init kasan_init_shadow(void)
*/
memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir));
dsb(ishst);
- cpu_replace_ttbr1(lm_alias(tmp_pg_dir), idmap_pg_dir);
+ cpu_replace_ttbr1(lm_alias(tmp_pg_dir));

clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);

@@ -265,7 +265,7 @@ static void __init kasan_init_shadow(void)
PAGE_KERNEL_RO));

memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
- cpu_replace_ttbr1(lm_alias(swapper_pg_dir), idmap_pg_dir);
+ cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
}

static void __init kasan_init_depth(void)
--
2.39.2