kernel-packages team mailing list archive

[Joseph Salisbury <joseph.salisbury@xxxxxxxxxxxxx>]

** Tags added: kernel-da-key utopic vivid

-- 
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/1425004

Title:
  powerpc/powernv: Ignore smt-enabled on Power8 and later

Status in linux package in Ubuntu:
  Confirmed
Status in linux source package in Utopic:
  Confirmed
Status in linux source package in Vivid:
  Confirmed

Bug description:
  Hi Ubuntu kernel folks,                                                                                
                                                                                                         
  This patch isn't quite upstream stable material, but might still be nice to                            
  have. It prevents smt-enabled=off on the kernel command line causing a hung                            
  system at boot.                                                                                        
                                                                                                         
  cheers                                                               

  ===

  From: Greg Kurz <gkurz@xxxxxxxxxxxxxxxxxx>                                                             
                                                                                                         
  Commit d70a54e2d08510a99b1f10eceeae6f2f7086e226 upstream.                                              
                                                                                                         
  Starting with POWER8, the subcore logic relies on all threads of a core                                
  being booted so that they can participate in split mode switches. So on                                
  those machines we ignore the smt_enabled_at_boot setting (smt-enabled on                               
  the kernel command line).                                                                              
                                                                                                         
  Signed-off-by: Greg Kurz <gkurz@xxxxxxxxxxxxxxxxxx>                                                    
  [mpe: Update comment and change log to be more precise]                                                
  Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>                                                   
  ---                                                                                                    
   arch/powerpc/platforms/powernv/smp.c | 16 +++++++++++++++-                                            
   1 file changed, 15 insertions(+), 1 deletion(-)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1425004/+subscriptions