diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2020-11-03 10:22:29 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-14 16:53:23 +0200 |
| commit | 8e6bcc566400170162d4765b0056e80df2a753bc (patch) | |
| tree | 3bc5bae8bf20160b7fb8775a5adfc00356cd5bb8 /arch/arm64/mm | |
| parent | ccbcdcd4af98055abc888972fcbcc0ce14c2522c (diff) | |
arm64: consistently use reserved_pg_dir
[ Upstream commit 833be850f1cabd0e3b5337c0fcab20a6e936dd48 ]
Depending on configuration options and specific code paths, we either
use the empty_zero_page or the configuration-dependent reserved_ttbr0
as a reserved value for TTBR{0,1}_EL1.
To simplify this code, let's always allocate and use the same
reserved_pg_dir, replacing reserved_ttbr0. Note that this is allocated
(and hence pre-zeroed), and is also marked as read-only in the kernel
Image mapping.
Keeping this separate from the empty_zero_page potentially helps with
robustness as the empty_zero_page is used in a number of cases where a
failure to map it read-only could allow it to become corrupted.
The (presently unused) swapper_pg_end symbol is also removed, and
comments are added wherever we rely on the offsets between the
pre-allocated pg_dirs to keep these cases easily identifiable.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201103102229.8542-1-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/proc.S | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index a1e0592d1fbc..13e78a5d8690 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -166,7 +166,7 @@ ENDPROC(cpu_do_switch_mm) .pushsection ".idmap.text", "awx" .macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2 - adrp \tmp1, empty_zero_page + adrp \tmp1, reserved_pg_dir phys_to_ttbr \tmp2, \tmp1 offset_ttbr1 \tmp2, \tmp1 msr ttbr1_el1, \tmp2 |