Kristina Martsenko f0e421b1bf arm64: documentation: document tagged pointer stack constraints ... Some kernel features don't currently work if a task puts a non-zero address tag in its stack pointer, frame pointer, or frame record entries (FP, LR). For example, with a tagged stack pointer, the kernel can't deliver signals to the process, and the task is killed instead. As another example, with a tagged frame pointer or frame records, perf fails to generate call graphs or resolve symbols. For now, just document these limitations, instead of finding and fixing everything that doesn't work, as it's not known if anyone needs to use tags in these places anyway. In addition, as requested by Dave Martin, generalize the limitations into a general kernel address tag policy, and refactor tagged-pointers.txt to include it. Fixes: d50240a5f6 ("arm64: mm: permit use of tagged pointers at EL0") Cc: <stable@vger.kernel.org> # 3.12.x- Reviewed-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>		2017-05-09 17:43:18 +01:00
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acpi_object_usage.txt	ARM64: ACPI: Update documentation for latest specification version	2016-06-21 16:26:09 +01:00
arm-acpi.txt	ARM64: ACPI: Update documentation for latest specification version	2016-06-21 16:26:09 +01:00
booting.txt	arm64: add the initrd region to the linear mapping explicitly	2016-04-14 16:20:45 +01:00
cpu-feature-registers.txt	arm64: v8.3: Support for weaker release consistency	2017-03-20 16:30:22 +00:00
legacy_instructions.txt
memory.txt
silicon-errata.txt	arm64: cpu_errata: Add capability to advertise Cortex-A73 erratum 858921	2017-04-07 11:22:08 +01:00
tagged-pointers.txt	arm64: documentation: document tagged pointer stack constraints	2017-05-09 17:43:18 +01:00