| Message ID | 1379705668-15621-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c index ee5b690..52e5758 100644 --- a/arch/powerpc/kernel/align.c +++ b/arch/powerpc/kernel/align.c @@ -764,6 +764,16 @@ int fix_alignment(struct pt_regs *regs) nb = aligninfo[instr].len; flags = aligninfo[instr].flags; + /* ldbrx/stdbrx overlap lfs/stfs in the DSISR unfortunately */ + if (IS_XFORM(instruction) && ((instruction >> 1) & 0x3ff) == 532) { + nb = 8; + flags = LD+SW; + } else if (IS_XFORM(instruction) && + ((instruction >> 1) & 0x3ff) == 660) { + nb = 8; + flags = ST+SW; + } + /* Byteswap little endian loads and stores */ swiz = 0; if (regs->msr & MSR_LE) {
This is a note to let you know that I have just added a patch titled powerpc: Handle unaligned ldbrx/stdbrx to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 4cb8eadfd5913cc951278d7ad470d75dedc7de2d Mon Sep 17 00:00:00 2001 From: Anton Blanchard <anton@samba.org> Date: Wed, 7 Aug 2013 02:01:19 +1000 Subject: [PATCH] powerpc: Handle unaligned ldbrx/stdbrx commit 230aef7a6a23b6166bd4003bfff5af23c9bd381f upstream. Normally when we haven't implemented an alignment handler for a load or store instruction the process will be terminated. The alignment handler uses the DSISR (or a pseudo one) to locate the right handler. Unfortunately ldbrx and stdbrx overlap lfs and stfs so we incorrectly think ldbrx is an lfs and stdbrx is an stfs. This bug is particularly nasty - instead of terminating the process we apply an incorrect fixup and continue on. With more and more overlapping instructions we should stop creating a pseudo DSISR and index using the instruction directly, but for now add a special case to catch ldbrx/stdbrx. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/powerpc/kernel/align.c | 10 ++++++++++ 1 file changed, 10 insertions(+) -- 1.8.3.2