linux_dsm_epyc7002/arch
Amit Daniel Kachhap 689eae42af arm64: mask PAC bits of __builtin_return_address
Functions like vmap() record how much memory has been allocated by their
callers, and callers are identified using __builtin_return_address(). Once
the kernel is using pointer-auth the return address will be signed. This
means it will not match any kernel symbol, and will vary between threads
even for the same caller.

The output of /proc/vmallocinfo in this case may look like,
0x(____ptrval____)-0x(____ptrval____)   20480 0x86e28000100e7c60 pages=4 vmalloc N0=4
0x(____ptrval____)-0x(____ptrval____)   20480 0x86e28000100e7c60 pages=4 vmalloc N0=4
0x(____ptrval____)-0x(____ptrval____)   20480 0xc5c78000100e7c60 pages=4 vmalloc N0=4

The above three 64bit values should be the same symbol name and not
different LR values.

Use the pre-processor to add logic to clear the PAC to
__builtin_return_address() callers. This patch adds a new file
asm/compiler.h and is transitively included via include/compiler_types.h on
the compiler command line so it is guaranteed to be loaded and the users of
this macro will not find a wrong version.

Helper macros ptrauth_kernel_pac_mask/ptrauth_clear_pac are created for
this purpose and added in this file. Existing macro ptrauth_user_pac_mask
moved from asm/pointer_auth.h.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-18 09:50:20 +00:00
..
alpha Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
arc arc: mm: add p?d_leaf() definitions 2020-02-04 03:05:24 +00:00
arm ARM: SoC fixes 2020-02-15 13:16:47 -08:00
arm64 arm64: mask PAC bits of __builtin_return_address 2020-03-18 09:50:20 +00:00
c6x Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-01-28 10:07:09 -08:00
csky csky: Replace <linux/clk-provider.h> by <linux/of_clk.h> 2020-02-23 12:48:55 +08:00
h8300 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-01-28 10:07:09 -08:00
hexagon Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-01-28 10:07:09 -08:00
ia64 proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2020-02-06 08:13:23 +00:00
microblaze Microblaze patches for 5.6-rc1 2020-02-04 11:58:07 +00:00
mips Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
nds32 TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
nios2 TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
openrisc TTY/Serial driver updates for 5.6-rc1 2020-01-29 10:13:27 -08:00
parisc Merge branch 'parisc-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2020-02-05 07:29:40 +00:00
powerpc powerpc/entry: Fix an #if which should be an #ifdef in entry_32.S 2020-02-19 10:35:22 +11:00
riscv Microblaze patches for 5.6-rc1 2020-02-04 11:58:07 +00:00
s390 s390/qdio: fill SBALEs with absolute addresses 2020-02-19 17:26:32 +01:00
sh proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
sparc Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
um proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
unicore32 MPX requires recompiling applications, which requires compiler support. 2020-01-30 16:11:50 -08:00
x86 Two fixes for the AMD MCE driver: 2020-02-22 18:02:10 -08:00
xtensa Xtensa updates for v5.6: 2020-02-07 12:22:29 -08:00
.gitignore
Kconfig asm-generic/tlb: provide MMU_GATHER_TABLE_FREE 2020-02-04 03:05:26 +00:00