x86/ldt: Reserve address-space range on 32 bit for the LDT

Reserve 2MB/4MB of address-space for mapping the LDT to user-space on 32
bit PTI kernels.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-34-git-send-email-joro@8bytes.org
This commit is contained in:
Joerg Roedel 2018-07-18 11:41:10 +02:00 committed by Thomas Gleixner
parent f59dbe9ca6
commit f3e48e546c
2 changed files with 14 additions and 2 deletions

View File

@ -50,13 +50,16 @@ extern bool __vmalloc_start_set; /* set once high_memory is set */
((FIXADDR_TOT_START - PAGE_SIZE * (CPU_ENTRY_AREA_PAGES + 1)) \
& PMD_MASK)
#define PKMAP_BASE \
#define LDT_BASE_ADDR \
((CPU_ENTRY_AREA_BASE - PAGE_SIZE) & PMD_MASK)
#define PKMAP_BASE \
((LDT_BASE_ADDR - PAGE_SIZE) & PMD_MASK)
#ifdef CONFIG_HIGHMEM
# define VMALLOC_END (PKMAP_BASE - 2 * PAGE_SIZE)
#else
# define VMALLOC_END (CPU_ENTRY_AREA_BASE - 2 * PAGE_SIZE)
# define VMALLOC_END (LDT_BASE_ADDR - 2 * PAGE_SIZE)
#endif
#define MODULES_VADDR VMALLOC_START

View File

@ -122,6 +122,9 @@ enum address_markers_idx {
VMALLOC_END_NR,
#ifdef CONFIG_HIGHMEM
PKMAP_BASE_NR,
#endif
#ifdef CONFIG_MODIFY_LDT_SYSCALL
LDT_NR,
#endif
CPU_ENTRY_AREA_NR,
FIXADDR_START_NR,
@ -135,6 +138,9 @@ static struct addr_marker address_markers[] = {
[VMALLOC_END_NR] = { 0UL, "vmalloc() End" },
#ifdef CONFIG_HIGHMEM
[PKMAP_BASE_NR] = { 0UL, "Persistent kmap() Area" },
#endif
#ifdef CONFIG_MODIFY_LDT_SYSCALL
[LDT_NR] = { 0UL, "LDT remap" },
#endif
[CPU_ENTRY_AREA_NR] = { 0UL, "CPU entry area" },
[FIXADDR_START_NR] = { 0UL, "Fixmap area" },
@ -609,6 +615,9 @@ static int __init pt_dump_init(void)
# endif
address_markers[FIXADDR_START_NR].start_address = FIXADDR_START;
address_markers[CPU_ENTRY_AREA_NR].start_address = CPU_ENTRY_AREA_BASE;
# ifdef CONFIG_MODIFY_LDT_SYSCALL
address_markers[LDT_NR].start_address = LDT_BASE_ADDR;
# endif
#endif
return 0;
}