[linux-kvm] UBUNTU: kvm: [Config] CONFIG_UNWINDER_FRAME_POINTER=y for amd64

From: Seth Forshee <seth.forshee@canonical.com>

BugLink: http://bugs.launchpad.net/bugs/1763107

During the rebase to 4.15 UNWINDER_ORC was chosen as the stack
unwinder as it promises a 5-10% performance improvement over
using UNWINDER_FRAME_POINTER. However it turns out to have a
couple of downsides. It adds a new requierment for building dkms
modules, and it does not produce the reliable stack traces
required for livepatch. Switch back to UNWINDER_FRAME_POINTER.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 debian.kvm/config/config.common.ubuntu | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

On Wed, Apr 11, 2018 at 10:41:52AM -0700, Kamal Mostafa wrote:
> From: Seth Forshee <seth.forshee@canonical.com>
> 
> BugLink: http://bugs.launchpad.net/bugs/1763107
> 
> During the rebase to 4.15 UNWINDER_ORC was chosen as the stack
> unwinder as it promises a 5-10% performance improvement over
> using UNWINDER_FRAME_POINTER. However it turns out to have a
> couple of downsides. It adds a new requierment for building dkms
> modules, and it does not produce the reliable stack traces
> required for livepatch. Switch back to UNWINDER_FRAME_POINTER.
> 
> Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
> Signed-off-by: Kamal Mostafa <kamal@canonical.com>

Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

> ---
>  debian.kvm/config/config.common.ubuntu | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/debian.kvm/config/config.common.ubuntu b/debian.kvm/config/config.common.ubuntu
> index 2e46f80..3f29b63 100644
> --- a/debian.kvm/config/config.common.ubuntu
> +++ b/debian.kvm/config/config.common.ubuntu
> @@ -724,6 +724,7 @@ CONFIG_FIX_EARLYCON_MEM=y
>  # CONFIG_FMC is not set
>  # CONFIG_FORTIFY_SOURCE is not set
>  # CONFIG_FPGA is not set
> +CONFIG_FRAME_POINTER=y
>  CONFIG_FRAME_WARN=2048
>  CONFIG_FREEZER=y
>  # CONFIG_FRONTSWAP is not set
> @@ -883,6 +884,7 @@ CONFIG_HAVE_PERF_REGS=y
>  CONFIG_HAVE_PERF_USER_STACK_DUMP=y
>  CONFIG_HAVE_RCU_TABLE_FREE=y
>  CONFIG_HAVE_REGS_AND_STACK_ACCESS_API=y
> +CONFIG_HAVE_RELIABLE_STACKTRACE=y
>  CONFIG_HAVE_SETUP_PER_CPU_AREA=y
>  CONFIG_HAVE_STACK_VALIDATION=y
>  CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
> @@ -2136,9 +2138,9 @@ CONFIG_UNIX=y
>  CONFIG_UNIX98_PTYS=y
>  # CONFIG_UNIX_DIAG is not set
>  # CONFIG_UNUSED_SYMBOLS is not set
> -# CONFIG_UNWINDER_FRAME_POINTER is not set
> +CONFIG_UNWINDER_FRAME_POINTER=y
>  # CONFIG_UNWINDER_GUESS is not set
> -CONFIG_UNWINDER_ORC=y
> +# CONFIG_UNWINDER_ORC is not set
>  # CONFIG_UPROBES is not set
>  CONFIG_USB_OHCI_LITTLE_ENDIAN=y
>  # CONFIG_USB_SUPPORT is not set
> -- 
> 2.7.4
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team

Applied to linux-kvm-bionic.

On Wed, Apr 11, 2018 at 10:41:52AM -0700, Kamal Mostafa wrote:
> From: Seth Forshee <seth.forshee@canonical.com>
> 
> BugLink: http://bugs.launchpad.net/bugs/1763107
> 
> During the rebase to 4.15 UNWINDER_ORC was chosen as the stack
> unwinder as it promises a 5-10% performance improvement over
> using UNWINDER_FRAME_POINTER. However it turns out to have a
> couple of downsides. It adds a new requierment for building dkms
> modules, and it does not produce the reliable stack traces
> required for livepatch. Switch back to UNWINDER_FRAME_POINTER.
> 
> Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
> Signed-off-by: Kamal Mostafa <kamal@canonical.com>
> ---
>  debian.kvm/config/config.common.ubuntu | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/debian.kvm/config/config.common.ubuntu b/debian.kvm/config/config.common.ubuntu
> index 2e46f80..3f29b63 100644
> --- a/debian.kvm/config/config.common.ubuntu
> +++ b/debian.kvm/config/config.common.ubuntu
> @@ -724,6 +724,7 @@ CONFIG_FIX_EARLYCON_MEM=y
>  # CONFIG_FMC is not set
>  # CONFIG_FORTIFY_SOURCE is not set
>  # CONFIG_FPGA is not set
> +CONFIG_FRAME_POINTER=y
>  CONFIG_FRAME_WARN=2048
>  CONFIG_FREEZER=y
>  # CONFIG_FRONTSWAP is not set
> @@ -883,6 +884,7 @@ CONFIG_HAVE_PERF_REGS=y
>  CONFIG_HAVE_PERF_USER_STACK_DUMP=y
>  CONFIG_HAVE_RCU_TABLE_FREE=y
>  CONFIG_HAVE_REGS_AND_STACK_ACCESS_API=y
> +CONFIG_HAVE_RELIABLE_STACKTRACE=y
>  CONFIG_HAVE_SETUP_PER_CPU_AREA=y
>  CONFIG_HAVE_STACK_VALIDATION=y
>  CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
> @@ -2136,9 +2138,9 @@ CONFIG_UNIX=y
>  CONFIG_UNIX98_PTYS=y
>  # CONFIG_UNIX_DIAG is not set
>  # CONFIG_UNUSED_SYMBOLS is not set
> -# CONFIG_UNWINDER_FRAME_POINTER is not set
> +CONFIG_UNWINDER_FRAME_POINTER=y
>  # CONFIG_UNWINDER_GUESS is not set
> -CONFIG_UNWINDER_ORC=y
> +# CONFIG_UNWINDER_ORC is not set
>  # CONFIG_UPROBES is not set
>  CONFIG_USB_OHCI_LITTLE_ENDIAN=y
>  # CONFIG_USB_SUPPORT is not set
> -- 
> 2.7.4
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team