Evolution-X-Devices/kernel_realme_sm7125
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

BACKPORT: x86/mm/cpa: Add set_direct_map_*() functions

Browse Source 
Add two new functions set_direct_map_default_noflush() and
set_direct_map_invalid_noflush() for setting the direct map alias for the
page to its default valid permissions and to an invalid state that cannot
be cached in a TLB, respectively. These functions do not flush the TLB.

Note, __kernel_map_pages() does something similar but flushes the TLB and
doesn't reset the permission bits to default on all architectures.

Also add an ARCH config ARCH_HAS_SET_DIRECT_MAP for specifying whether
these have an actual implementation or a default empty one.

Change-Id: I0f5c4b3cac1c937ccab68c3278ce8ea3ca833032
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <akpm@linux-foundation.org>
Cc: <ard.biesheuvel@linaro.org>
Cc: <deneen.t.dock@intel.com>
Cc: <kernel-hardening@lists.openwall.com>
Cc: <kristen@linux.intel.com>
Cc: <linux_dti@icloud.com>
Cc: <will.deacon@arm.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: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190426001143.4983-15-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Rick Edgecombe
2019-04-25 17:11:34 -07:00
committed by theshaenix
parent ffbad4b377
commit 2959382ba1
5 changed files with 30 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
arch/Kconfig
View File

@@ -243,6 +243,10 @@ config ARCH_HAS_SET_MEMORY
config ARCH_HAS_CPU_FINALIZE_INIT
bool
# Select if arch has all set_direct_map_invalid/default() functions
config ARCH_HAS_SET_DIRECT_MAP
bool
# Select if arch init_task initializer is different to init/init_task.c
config ARCH_INIT_TASK
bool

1
arch/x86/Kconfig
View File

@@ -60,6 +60,7 @@ config X86
select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_SG_CHAIN
select ARCH_HAS_SET_DIRECT_MAP
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_UBSAN_SANITIZE_ALL

3
arch/x86/include/asm/set_memory.h
View File

@@ -84,6 +84,9 @@ int set_pages_nx(struct page *page, int numpages);
int set_pages_ro(struct page *page, int numpages);
int set_pages_rw(struct page *page, int numpages);
int set_direct_map_invalid_noflush(struct page *page);
int set_direct_map_default_noflush(struct page *page);
extern int kernel_set_to_readonly;
void set_kernel_text_rw(void);
void set_kernel_text_ro(void);

14
arch/x86/mm/pageattr.c
View File

@@ -1976,8 +1976,6 @@ int set_pages_rw(struct page *page, int numpages)
return set_memory_rw(addr, numpages);
}
#ifdef CONFIG_DEBUG_PAGEALLOC
static int __set_pages_p(struct page *page, int numpages)
{
unsigned long tempaddr = (unsigned long) page_address(page);
@@ -2016,6 +2014,17 @@ static int __set_pages_np(struct page *page, int numpages)
return __change_page_attr_set_clr(&cpa, 0);
}
int set_direct_map_invalid_noflush(struct page *page)
{
return __set_pages_np(page, 1);
}
int set_direct_map_default_noflush(struct page *page)
{
return __set_pages_p(page, 1);
}
#ifdef CONFIG_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
if (PageHighMem(page))
@@ -2049,7 +2058,6 @@ void __kernel_map_pages(struct page *page, int numpages, int enable)
}
#ifdef CONFIG_HIBERNATION
bool kernel_page_present(struct page *page)
{
unsigned int level;

11
include/linux/set_memory.h
View File

@@ -17,4 +17,15 @@ static inline int set_memory_x(unsigned long addr, int numpages) { return 0; }
static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; }
#endif
#ifndef CONFIG_ARCH_HAS_SET_DIRECT_MAP
static inline int set_direct_map_invalid_noflush(struct page *page)
{
return 0;
}
static inline int set_direct_map_default_noflush(struct page *page)
{
return 0;
}
#endif
#endif /* _LINUX_SET_MEMORY_H_ */