Commit 3a179306 authored Aug 28, 2020 by Pingfan Liu Committed by Will Deacon Sep 11, 2020

Documentation/kvm/arm: improve description of HVC_SOFT_RESTART



Besides disabling MMU, HVC_SOFT_RESTART also clears I+D bits. These behaviors
are what kexec-reboot expects, so describe it more precisely.

Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-doc@vger.kernel.org
Cc: kvmarm@lists.cs.columbia.edu
Link: https://lore.kernel.org/r/1598621998-20563-2-git-send-email-kernelfans@gmail.com


To: linux-arm-kernel@lists.infradead.org
Signed-off-by: Will Deacon <will@kernel.org>

parent 72789a4a

Documentation/virt/kvm/arm/hyp-abi.rst

+3 −3

Original line number	Diff line number	Diff line
		@@ -54,9 +54,9 @@ these functions (see arch/arm{,64}/include/asm/virt.h):
		x3 = x1's value when entering the next payload (arm64)
		x4 = x2's value when entering the next payload (arm64)

		Mask all exceptions, disable the MMU, move the arguments into place
		(arm64 only), and jump to the restart address while at HYP/EL2. This
		hypercall is not expected to return to its caller.
		Mask all exceptions, disable the MMU, clear I+D bits, move the arguments
		into place (arm64 only), and jump to the restart address while at HYP/EL2.
		This hypercall is not expected to return to its caller.

		Any other value of r0/x0 triggers a hypervisor-specific handling,
		which is not documented here.

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