diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2019-12-10 11:19:15 +0000 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-09-04 12:46:07 +0100 |
| commit | af5ce95282dc99d08a27a407a02c763dde1c5558 (patch) | |
| tree | f47b4662e6307e2f9ca8d7d9126760216afadd4b /arch/arm64/kernel/process.c | |
| parent | 1c101da8b971a36695319dce7a24711dc567a0dd (diff) | |
arm64: mte: Allow user control of the generated random tags via prctl()
The IRG, ADDG and SUBG instructions insert a random tag in the resulting
address. Certain tags can be excluded via the GCR_EL1.Exclude bitmap
when, for example, the user wants a certain colour for freed buffers.
Since the GCR_EL1 register is not accessible at EL0, extend the
prctl(PR_SET_TAGGED_ADDR_CTRL) interface to include a 16-bit field in
the first argument for controlling which tags can be generated by the
above instruction (an include rather than exclude mask). Note that by
default all non-zero tags are excluded. This setting is per-thread.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/process.c')
| -rw-r--r-- | arch/arm64/kernel/process.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index bb759b88d44a..c80383f30d6a 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -649,7 +649,7 @@ long set_tagged_addr_ctrl(unsigned long arg) return -EINVAL; if (system_supports_mte()) - valid_mask |= PR_MTE_TCF_MASK; + valid_mask |= PR_MTE_TCF_MASK | PR_MTE_TAG_MASK; if (arg & ~valid_mask) return -EINVAL; |