** Tags added: kernel-bug-break-fix ** Description changed:
- == SRU Justification == Commit 09ca4c9b5958 introduced a bug in v4.8-rc2. The bug is that an error happens in CPU frequency reporting when nominal and min pstates are the same (cpufreq). Commit 3fa4680b8 fixes this issue. Commit 3fa4680b8 is in mailine as of v4.16-rc1 and has been cc'd to upstream stable. == Fix == commit 3fa4680b860bf48b437d6a2c039789c4abe202ae Author: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com> Date: Fri Jan 12 12:43:53 2018 +0530 - cpufreq: powernv: Dont assume distinct pstate values for nominal and + cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin == Regression Potential == - Low. This commit been cc'd to upstream stable, so it has had additional + Low. This commit been cc'd to upstream stable, so it has had additional upstream review. == Test Case == A test kernel was built with this patch and tested by the original bug reporter. The bug reporter states the test kernel resolved the bug. - - == Comment: #0 - Shilpasri G. Bhat +++ This bug was initially created as a clone of Bug #163527 +++ ---Problem Description--- Error in CPU frequency reporting when nominal and min pstates are same The patch for this issue is accepted to linux-next as 3fa4680b860bf48b437d6a2c039789c4abe202ae cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin Some OpenPOWER boxes can have same pstate values for nominal and pmin pstates. In these boxes the current code will not initialize 'powernv_pstate_info.min' variable and result in erroneous CPU frequency reporting. This patch fixes this problem. Fixes: 09ca4c9b5958 (cpufreq: powernv: Replacing pstate_id with frequency table index) Reported-by: Alvin Wang <wan...@tw.ibm.com> Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.ku...@linaro.org> Cc: 4.8+ <sta...@vger.kernel.org> # 4.8+ Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux- pm.git/commit/drivers/cpufreq/powernv-cpufreq.c?h=linux- next&id=3fa4680b860bf48b437d6a2c039789c4abe202ae + + break-fix: - cf0de9a0d52ff64bcb6b20b6fa4b5d3eb4637719 + break-fix: - 3fa4680b860bf48b437d6a2c039789c4abe202ae ** Changed in: linux (Ubuntu Bionic) Status: In Progress => Fix Committed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1746174 Title: Error in CPU frequency reporting when nominal and min pstates are same (cpufreq) Status in The Ubuntu-power-systems project: Incomplete Status in linux package in Ubuntu: Fix Committed Status in linux source package in Artful: In Progress Status in linux source package in Bionic: Fix Committed Bug description: == SRU Justification == Commit 09ca4c9b5958 introduced a bug in v4.8-rc2. The bug is that an error happens in CPU frequency reporting when nominal and min pstates are the same (cpufreq). Commit 3fa4680b8 fixes this issue. Commit 3fa4680b8 is in mailine as of v4.16-rc1 and has been cc'd to upstream stable. == Fix == commit 3fa4680b860bf48b437d6a2c039789c4abe202ae Author: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com> Date: Fri Jan 12 12:43:53 2018 +0530 cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin == Regression Potential == Low. This commit been cc'd to upstream stable, so it has had additional upstream review. == Test Case == A test kernel was built with this patch and tested by the original bug reporter. The bug reporter states the test kernel resolved the bug. == Comment: #0 - Shilpasri G. Bhat +++ This bug was initially created as a clone of Bug #163527 +++ ---Problem Description--- Error in CPU frequency reporting when nominal and min pstates are same The patch for this issue is accepted to linux-next as 3fa4680b860bf48b437d6a2c039789c4abe202ae cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin Some OpenPOWER boxes can have same pstate values for nominal and pmin pstates. In these boxes the current code will not initialize 'powernv_pstate_info.min' variable and result in erroneous CPU frequency reporting. This patch fixes this problem. Fixes: 09ca4c9b5958 (cpufreq: powernv: Replacing pstate_id with frequency table index) Reported-by: Alvin Wang <wan...@tw.ibm.com> Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com> Acked-by: Viresh Kumar <viresh.ku...@linaro.org> Cc: 4.8+ <sta...@vger.kernel.org> # 4.8+ Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux- pm.git/commit/drivers/cpufreq/powernv-cpufreq.c?h=linux- next&id=3fa4680b860bf48b437d6a2c039789c4abe202ae break-fix: - cf0de9a0d52ff64bcb6b20b6fa4b5d3eb4637719 break-fix: - 3fa4680b860bf48b437d6a2c039789c4abe202ae To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1746174/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp