Messages in this thread | | | Date | Wed, 6 Jan 2016 12:15:25 +0000 | From | Catalin Marinas <> | Subject | Re: [PATCH 1/2] arm64: entry: remove pointless SPSR mode check |
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On Tue, Jan 05, 2016 at 05:33:34PM +0000, Mark Rutland wrote: > In work_pending we may skip work if the stacked SPSR value represents > anything other than an EL0 context. We then immediately invoke the > kernel_exit 0 macro as part of ret_to_user, assuming a return to EL0. > This is somewhat confusing. > > We use work_pending as part of the ret_to_user/ret_fast_syscall state > machine. We only use ret_fast_syscall in the return from an SVC issued > from EL0. We use ret_to_user for return from EL0 exception handlers and > also for return from ret_from_fork in the case the task was not a kernel > thread (i.e. it is a user task). > > Thus in all cases the stacked SPSR value must represent an EL0 context, > and the check is redundant. This patch removes it, along with the now > unused no_work_pending label. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Chris Metcalf <cmetcalf@ezchip.com> > Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
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