mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
arm64 fixes:
- Report correct timer frequency to userspace when trapping CNTFRQ_EL0 - Fix race with hardware page table updates when updating access flags - Silence clang overflow warning in VA_START and PAGE_OFFSET calculations -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAABCgAGBQJZhIc7AAoJELescNyEwWM0EaUH/0f1/MnKwZHAUoSOWrZynKna 0y59hNvlr47FCGxaMVSVWq/+mtSqxsQTPyLkLSULh8PR7OEwjq5qLxLMhFWF/7B4 /nmAGhFOYHDR95/0Mo0cMOMyamIvGPIqd304yld0P13S5z26UdRCoTrWgeKFJ2sm wcKCJeAK+U4NZbASNthDKH7Mo0lM25oLIJ8gqj4o0NrxyZr86mXVTypV/nM82qdm WRMFqGh5iRrmnGSCajgcTjqnYkFOYwHirKvdrV68+GFOYqVIS+9+RdwSnRNOZ9hl MsIOUDRn3doHDe4tK9NcQlLoaRIqA9fM4+94XGJu+8uUNfDRYMueO6XUvGmnmOQ= =FER5 -----END PGP SIGNATURE----- Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "Here are some more arm64 fixes for 4.13. The main one is the PTE race with the hardware walker, but there are a couple of other things too. - Report correct timer frequency to userspace when trapping CNTFRQ_EL0 - Fix race with hardware page table updates when updating access flags - Silence clang overflow warning in VA_START and PAGE_OFFSET calculations" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: avoid overflow in VA_START and PAGE_OFFSET arm64: Fix potential race with hardware DBM in ptep_set_access_flags() arm64: Use arch_timer_get_rate when trapping CNTFRQ_EL0
This commit is contained in:
commit
b3c6858fb1
3 changed files with 13 additions and 10 deletions
|
@ -64,8 +64,10 @@
|
|||
* TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
|
||||
*/
|
||||
#define VA_BITS (CONFIG_ARM64_VA_BITS)
|
||||
#define VA_START (UL(0xffffffffffffffff) << VA_BITS)
|
||||
#define PAGE_OFFSET (UL(0xffffffffffffffff) << (VA_BITS - 1))
|
||||
#define VA_START (UL(0xffffffffffffffff) - \
|
||||
(UL(1) << VA_BITS) + 1)
|
||||
#define PAGE_OFFSET (UL(0xffffffffffffffff) - \
|
||||
(UL(1) << (VA_BITS - 1)) + 1)
|
||||
#define KIMAGE_VADDR (MODULES_END)
|
||||
#define MODULES_END (MODULES_VADDR + MODULES_VSIZE)
|
||||
#define MODULES_VADDR (VA_START + KASAN_SHADOW_SIZE)
|
||||
|
|
|
@ -523,7 +523,7 @@ static void cntfrq_read_handler(unsigned int esr, struct pt_regs *regs)
|
|||
{
|
||||
int rt = (esr & ESR_ELx_SYS64_ISS_RT_MASK) >> ESR_ELx_SYS64_ISS_RT_SHIFT;
|
||||
|
||||
pt_regs_write_reg(regs, rt, read_sysreg(cntfrq_el0));
|
||||
pt_regs_write_reg(regs, rt, arch_timer_get_rate());
|
||||
regs->pc += 4;
|
||||
}
|
||||
|
||||
|
|
|
@ -163,26 +163,27 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
|
|||
/* only preserve the access flags and write permission */
|
||||
pte_val(entry) &= PTE_AF | PTE_WRITE | PTE_DIRTY;
|
||||
|
||||
/*
|
||||
* PTE_RDONLY is cleared by default in the asm below, so set it in
|
||||
* back if necessary (read-only or clean PTE).
|
||||
*/
|
||||
/* set PTE_RDONLY if actual read-only or clean PTE */
|
||||
if (!pte_write(entry) || !pte_sw_dirty(entry))
|
||||
pte_val(entry) |= PTE_RDONLY;
|
||||
|
||||
/*
|
||||
* Setting the flags must be done atomically to avoid racing with the
|
||||
* hardware update of the access/dirty state.
|
||||
* hardware update of the access/dirty state. The PTE_RDONLY bit must
|
||||
* be set to the most permissive (lowest value) of *ptep and entry
|
||||
* (calculated as: a & b == ~(~a | ~b)).
|
||||
*/
|
||||
pte_val(entry) ^= PTE_RDONLY;
|
||||
asm volatile("// ptep_set_access_flags\n"
|
||||
" prfm pstl1strm, %2\n"
|
||||
"1: ldxr %0, %2\n"
|
||||
" and %0, %0, %3 // clear PTE_RDONLY\n"
|
||||
" eor %0, %0, %3 // negate PTE_RDONLY in *ptep\n"
|
||||
" orr %0, %0, %4 // set flags\n"
|
||||
" eor %0, %0, %3 // negate final PTE_RDONLY\n"
|
||||
" stxr %w1, %0, %2\n"
|
||||
" cbnz %w1, 1b\n"
|
||||
: "=&r" (old_pteval), "=&r" (tmp), "+Q" (pte_val(*ptep))
|
||||
: "L" (~PTE_RDONLY), "r" (pte_val(entry)));
|
||||
: "L" (PTE_RDONLY), "r" (pte_val(entry)));
|
||||
|
||||
flush_tlb_fix_spurious_fault(vma, address);
|
||||
return 1;
|
||||
|
|
Loading…
Reference in a new issue