[4.2.y-ckt stable] Patch "perf tools: Fix perf regs mask generation" has been added to the 4.2.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    perf tools: Fix perf regs mask generation

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    https://git.launchpad.net/~canonical-kernel/linux/+git/linux-stable-ckt/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt12.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From b6cadf31ec35d4eced46d68bec8c1fcb012cfc36 Mon Sep 17 00:00:00 2001
From: "Naveen N. Rao" <naveen.n.rao at linux.vnet.ibm.com>
Date: Thu, 28 Apr 2016 15:01:10 +0530
Subject: perf tools: Fix perf regs mask generation

commit f47822078dece7189cad0a5f472f148e5e916736 upstream.

On some architectures (powerpc in particular), the number of registers
exceeds what can be represented in an integer bitmask. Ensure we
generate the proper bitmask on such platforms.

Fixes: 71ad0f5e4 ("perf tools: Support for DWARF CFI unwinding on post processing")
Signed-off-by: Naveen N. Rao <naveen.n.rao at linux.vnet.ibm.com>
Acked-by: Arnaldo Carvalho de Melo <acme at redhat.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 tools/perf/util/perf_regs.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/perf_regs.c b/tools/perf/util/perf_regs.c
index 43168fb..2fb6f2a 100644
--- a/tools/perf/util/perf_regs.c
+++ b/tools/perf/util/perf_regs.c
@@ -7,18 +7,18 @@ int perf_reg_value(u64 *valp, struct regs_dump *regs, int id)
 	int i, idx = 0;
 	u64 mask = regs->mask;

-	if (regs->cache_mask & (1 << id))
+	if (regs->cache_mask & (1ULL << id))
 		goto out;

-	if (!(mask & (1 << id)))
+	if (!(mask & (1ULL << id)))
 		return -EINVAL;

 	for (i = 0; i < id; i++) {
-		if (mask & (1 << i))
+		if (mask & (1ULL << i))
 			idx++;
 	}

-	regs->cache_mask |= (1 << id);
+	regs->cache_mask |= (1ULL << id);
 	regs->cache_regs[id] = regs->regs[idx];

 out:
--
2.7.4