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x86/tlb: Restrict access to tlbstate

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Hide tlbstate, flush_tlb_info and related helpers when tlbflush.h is
included from a module. Modules have absolutely no business with these
internals.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200421092600.328438734@linutronix.de
This commit is contained in:
Thomas Gleixner 2020-04-21 11:20:43 +02:00 committed by Borislav Petkov
parent 8a29204f3e
commit bfe3d8f631
2 changed files with 49 additions and 48 deletions
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96
arch/x86/include/asm/tlbflush.h
View File

@ -13,19 +13,46 @@
#include <asm/pti.h>
#include <asm/processor-flags.h>
struct flush_tlb_info;
void __flush_tlb_all(void);
void flush_tlb_local(void);
void flush_tlb_one_user(unsigned long addr);
void flush_tlb_one_kernel(unsigned long addr);
void flush_tlb_others(const struct cpumask *cpumask,
const struct flush_tlb_info *info);
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#endif
#define TLB_FLUSH_ALL -1UL
void cr4_update_irqsoff(unsigned long set, unsigned long clear);
unsigned long cr4_read_shadow(void);
/* Set in this cpu's CR4. */
static inline void cr4_set_bits_irqsoff(unsigned long mask)
{
cr4_update_irqsoff(mask, 0);
}
/* Clear in this cpu's CR4. */
static inline void cr4_clear_bits_irqsoff(unsigned long mask)
{
cr4_update_irqsoff(0, mask);
}
/* Set in this cpu's CR4. */
static inline void cr4_set_bits(unsigned long mask)
{
unsigned long flags;
local_irq_save(flags);
cr4_set_bits_irqsoff(mask);
local_irq_restore(flags);
}
/* Clear in this cpu's CR4. */
static inline void cr4_clear_bits(unsigned long mask)
{
unsigned long flags;
local_irq_save(flags);
cr4_clear_bits_irqsoff(mask);
local_irq_restore(flags);
}
#ifndef MODULE
/*
* 6 because 6 should be plenty and struct tlb_state will fit in two cache
* lines.
@ -129,54 +156,17 @@ DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);
bool nmi_uaccess_okay(void);
#define nmi_uaccess_okay nmi_uaccess_okay
void cr4_update_irqsoff(unsigned long set, unsigned long clear);
unsigned long cr4_read_shadow(void);
/* Initialize cr4 shadow for this CPU. */
static inline void cr4_init_shadow(void)
{
this_cpu_write(cpu_tlbstate.cr4, __read_cr4());
}
/* Set in this cpu's CR4. */
static inline void cr4_set_bits_irqsoff(unsigned long mask)
{
cr4_update_irqsoff(mask, 0);
}
/* Clear in this cpu's CR4. */
static inline void cr4_clear_bits_irqsoff(unsigned long mask)
{
cr4_update_irqsoff(0, mask);
}
/* Set in this cpu's CR4. */
static inline void cr4_set_bits(unsigned long mask)
{
unsigned long flags;
local_irq_save(flags);
cr4_set_bits_irqsoff(mask);
local_irq_restore(flags);
}
/* Clear in this cpu's CR4. */
static inline void cr4_clear_bits(unsigned long mask)
{
unsigned long flags;
local_irq_save(flags);
cr4_clear_bits_irqsoff(mask);
local_irq_restore(flags);
}
extern unsigned long mmu_cr4_features;
extern u32 *trampoline_cr4_features;
extern void initialize_tlbstate_and_flush(void);
#define TLB_FLUSH_ALL -1UL
/*
* TLB flushing:
*
@ -215,6 +205,16 @@ struct flush_tlb_info {
bool freed_tables;
};
void flush_tlb_local(void);
void flush_tlb_one_user(unsigned long addr);
void flush_tlb_one_kernel(unsigned long addr);
void flush_tlb_others(const struct cpumask *cpumask,
const struct flush_tlb_info *info);
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#endif
#define flush_tlb_mm(mm) \
flush_tlb_mm_range(mm, 0UL, TLB_FLUSH_ALL, 0UL, true)
@ -255,4 +255,6 @@ static inline void arch_tlbbatch_add_mm(struct arch_tlbflush_unmap_batch *batch,
extern void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch);
#endif /* !MODULE */
#endif /* _ASM_X86_TLBFLUSH_H */

1
arch/x86/mm/init.c
View File

@ -992,7 +992,6 @@ __visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = {
.next_asid = 1,
.cr4 = ~0UL, /* fail hard if we screw up cr4 shadow initialization */
};
EXPORT_PER_CPU_SYMBOL(cpu_tlbstate);
void update_cache_mode_entry(unsigned entry, enum page_cache_mode cache)
{