Re: [PATCH 03/18] arm64: hyp-stub: Move elx_sync into the vectors
From: Marc Zyngier <maz@kernel.org>
Date: 2021-05-27 15:54:41
Also in:
kexec, linux-mm, lkml
On Thu, 27 May 2021 16:05:11 +0100, Pavel Tatashin [off-list ref] wrote:
quoted hunk ↗ jump to hunk
The hyp-stub's elx_sync code fits in the vector. With this, all of the hyp-stubs behaviour is contained in its vectors. This lets kexec and hibernate copy the hyp-stub when they need its behaviour, instead of re-implementing it. Co-developed-by: James Morse <james.morse@arm.com> Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> --- arch/arm64/kernel/hyp-stub.S | 64 +++++++++++++++++++----------------- 1 file changed, 33 insertions(+), 31 deletions(-)diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 18a97bee3779..86af6c4e52b9 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S@@ -21,6 +21,37 @@ SYM_CODE_START_LOCAL(\label) .align 7 b \label SYM_CODE_END(\label) +.endm + +.macro elx_sync_vector label +SYM_CODE_START_LOCAL(\label) + .align 7 + cmp x0, #HVC_SET_VECTORS + b.ne 1f + msr vbar_el2, x1 + b 9f + +1: cmp x0, #HVC_VHE_RESTART + b.eq mutate_to_vhe
Now that this has turned into a macro, what are the guarantees that mutate_to_vhe will be within reach of the site where this macro is expanded? It does work here, but what about the other expansion sites that will show up later in the series? What was wrong with directly branching to the original call site? Nothing in the commit message explains it. Thanks, M. -- Without deviation from the norm, progress is not possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel