From 3a1793066fdfbbd657d9591cc03d6e1b6634a587 Mon Sep 17 00:00:00 2001 From: Pingfan Liu Date: Fri, 28 Aug 2020 21:39:58 +0800 Subject: [PATCH] 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 Cc: James Morse Cc: Marc Zyngier Cc: Geoff Levand Cc: Catalin Marinas Cc: Will Deacon Cc: Julien Thierry Cc: Suzuki K Poulose 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 --- Documentation/virt/kvm/arm/hyp-abi.rst | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Documentation/virt/kvm/arm/hyp-abi.rst b/Documentation/virt/kvm/arm/hyp-abi.rst index d9eba93aa364..83cadd8186fa 100644 --- a/Documentation/virt/kvm/arm/hyp-abi.rst +++ b/Documentation/virt/kvm/arm/hyp-abi.rst @@ -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.