diff options
| author | Will Deacon <will.deacon@arm.com> | 2017-11-14 14:07:40 +0000 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2017-12-11 13:40:47 +0000 |
| commit | c7b9adaf85f818d747eeff5145eb4095ccd587fb (patch) | |
| tree | 9c4bd42693c9f41f676c149e87b74f764b38b3b5 /arch/arm64/kernel/vmlinux.lds.S | |
| parent | 9b0de864b5bc298ea53005ad812f3386f81aee9c (diff) | |
arm64: entry: Add exception trampoline page for exceptions from EL0
To allow unmapping of the kernel whilst running at EL0, we need to
point the exception vectors at an entry trampoline that can map/unmap
the kernel on entry/exit respectively.
This patch adds the trampoline page, although it is not yet plugged
into the vector table and is therefore unused.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Tested-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel/vmlinux.lds.S')
| -rw-r--r-- | arch/arm64/kernel/vmlinux.lds.S | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 7da3e5c366a0..6b4260f22aab 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -57,6 +57,17 @@ jiffies = jiffies_64; #define HIBERNATE_TEXT #endif +#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 +#define TRAMP_TEXT \ + . = ALIGN(PAGE_SIZE); \ + VMLINUX_SYMBOL(__entry_tramp_text_start) = .; \ + *(.entry.tramp.text) \ + . = ALIGN(PAGE_SIZE); \ + VMLINUX_SYMBOL(__entry_tramp_text_end) = .; +#else +#define TRAMP_TEXT +#endif + /* * The size of the PE/COFF section that covers the kernel image, which * runs from stext to _edata, must be a round multiple of the PE/COFF @@ -113,6 +124,7 @@ SECTIONS HYPERVISOR_TEXT IDMAP_TEXT HIBERNATE_TEXT + TRAMP_TEXT *(.fixup) *(.gnu.warning) . = ALIGN(16); @@ -214,6 +226,11 @@ SECTIONS . += RESERVED_TTBR0_SIZE; #endif +#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 + tramp_pg_dir = .; + . += PAGE_SIZE; +#endif + __pecoff_data_size = ABSOLUTE(. - __initdata_begin); _end = .; |