x86/mm: Initialize PGD cache during mm initialization

Poking-mm initialization might require to duplicate the PGD in early
stage. Initialize the PGD cache earlier to prevent boot failures.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4fc19708b1 ("x86/alternatives: Initialize temporary mm for patching")
Link: http://lkml.kernel.org/r/20190505011124.39692-1-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Nadav Amit 2019-05-04 18:11:24 -07:00 committed by Ingo Molnar
parent 3950746d9d
commit caa8413601
3 changed files with 11 additions and 4 deletions

View File

@ -373,14 +373,14 @@ static void pgd_prepopulate_user_pmd(struct mm_struct *mm,
static struct kmem_cache *pgd_cache;
static int __init pgd_cache_init(void)
void __init pgd_cache_init(void)
{
/*
* When PAE kernel is running as a Xen domain, it does not use
* shared kernel pmd. And this requires a whole page for pgd.
*/
if (!SHARED_KERNEL_PMD)
return 0;
return;
/*
* when PAE kernel is not running as a Xen domain, it uses
@ -390,9 +390,7 @@ static int __init pgd_cache_init(void)
*/
pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_ALIGN,
SLAB_PANIC, NULL);
return 0;
}
core_initcall(pgd_cache_init);
static inline pgd_t *_pgd_alloc(void)
{
@ -420,6 +418,10 @@ static inline void _pgd_free(pgd_t *pgd)
}
#else
void __init pgd_cache_init(void)
{
}
static inline pgd_t *_pgd_alloc(void)
{
return (pgd_t *)__get_free_pages(PGALLOC_GFP, PGD_ALLOCATION_ORDER);

View File

@ -1126,6 +1126,8 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
static inline void init_espfix_bsp(void) { }
#endif
extern void __init pgd_cache_init(void);
#ifndef __HAVE_ARCH_PFN_MODIFY_ALLOWED
static inline bool pfn_modify_allowed(unsigned long pfn, pgprot_t prot)
{

View File

@ -506,6 +506,8 @@ void __init __weak mem_encrypt_init(void) { }
void __init __weak poking_init(void) { }
void __init __weak pgd_cache_init(void) { }
bool initcall_debug;
core_param(initcall_debug, initcall_debug, bool, 0644);
@ -537,6 +539,7 @@ static void __init mm_init(void)
init_espfix_bsp();
/* Should be run after espfix64 is set up. */
pti_init();
pgd_cache_init();
}
void __init __weak arch_call_rest_init(void)