| Message ID | 1310209058-20980-2-git-send-email-tixy@yxit.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, 9 Jul 2011, Tixy wrote: > From: Jon Medhurst <tixy@yxit.co.uk> > > The implementation of svc_exit didn't take into account any stack hole > created by svc_entry; as happens with the undef handler when kprobes are > configured. The fix is to read the saved value of SP rather than trying > to calculate it. > > Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> > --- > arch/arm/kernel/entry-header.S | 12 +++++------- > 1 files changed, 5 insertions(+), 7 deletions(-) > > diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S > index 051166c..83e29ad 100644 > --- a/arch/arm/kernel/entry-header.S > +++ b/arch/arm/kernel/entry-header.S > @@ -121,15 +121,13 @@ > .endm > #else /* CONFIG_THUMB2_KERNEL */ > .macro svc_exit, rpsr > + ldr lr, [sp, #S_SP] @ top of the stack > + ldrd r0, r1, [sp, #S_LR] @ calling lr and pc > clrex @ clear the exclusive monitor > - ldr r0, [sp, #S_SP] @ top of the stack > - ldr r1, [sp, #S_PC] @ return address > - tst r0, #4 @ orig stack 8-byte aligned? > - stmdb r0, {r1, \rpsr} @ rfe context > + stmdb lr!, {r0, r1, \rpsr} @ calling lr and rfe context > ldmia sp, {r0 - r12} > - ldr lr, [sp, #S_LR] > - addeq sp, sp, #S_FRAME_SIZE - 8 @ aligned > - addne sp, sp, #S_FRAME_SIZE - 4 @ not aligned > + mov sp, lr > + ldr lr, [sp], #4 > rfeia sp! > .endm > > -- > 1.7.2.5 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S index 051166c..83e29ad 100644 --- a/arch/arm/kernel/entry-header.S +++ b/arch/arm/kernel/entry-header.S @@ -121,15 +121,13 @@ .endm #else /* CONFIG_THUMB2_KERNEL */ .macro svc_exit, rpsr + ldr lr, [sp, #S_SP] @ top of the stack + ldrd r0, r1, [sp, #S_LR] @ calling lr and pc clrex @ clear the exclusive monitor - ldr r0, [sp, #S_SP] @ top of the stack - ldr r1, [sp, #S_PC] @ return address - tst r0, #4 @ orig stack 8-byte aligned? - stmdb r0, {r1, \rpsr} @ rfe context + stmdb lr!, {r0, r1, \rpsr} @ calling lr and rfe context ldmia sp, {r0 - r12} - ldr lr, [sp, #S_LR] - addeq sp, sp, #S_FRAME_SIZE - 8 @ aligned - addne sp, sp, #S_FRAME_SIZE - 4 @ not aligned + mov sp, lr + ldr lr, [sp], #4 rfeia sp! .endm