| Message ID | 1302210948-5799-2-git-send-email-herton.krzesinski@canonical.com |
|---|---|
| State | New |
| Headers | show |
On 04/07/2011 11:15 PM, Herton Ronaldo Krzesinski wrote: > From: H. Peter Anvin <hpa@linux.intel.com> > > Restore the initialization of mmu_cr4_features during boot, which was > removed without comment in checkin e5f15b45ddf3afa2bbbb10c7ea34fb32b6de0a0e > > x86: Cleanup highmap after brk is concluded > > thereby breaking resume from hibernate. This restores previous > functionality in approximately the same place, and corrects the > reading of %cr4 on pre-CPUID hardware (%cr4 exists if and only if > CPUID is supported.) > > However, part of the problem is that the hibernate suspend/resume > sequence should manage the save/restore of %cr4 explicitly. > > Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> > Cc: Rafael J. Wysocki <rjw@sisk.pl> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: Yinghai Lu <yinghai@kernel.org> > LKML-Reference: <201104020154.57136.rjw@sisk.pl> > (cherry picked from commit 4da9484bdece39ab0b098fa711e095e3e9fc8684) > Tested-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> > BugLink: http://bugs.launchpad.net/bugs/752870 > Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> > --- > arch/x86/kernel/setup.c | 5 +++++ > 1 files changed, 5 insertions(+), 0 deletions(-) > > diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c > index e543fe9..4e59873 100644 > --- a/arch/x86/kernel/setup.c > +++ b/arch/x86/kernel/setup.c > @@ -1013,6 +1013,11 @@ void __init setup_arch(char **cmdline_p) > paging_init(); > x86_init.paging.pagetable_setup_done(swapper_pg_dir); > > + if (boot_cpu_data.cpuid_level >= 0) { > + /* A CPU has %cr4 if and only if it has CPUID */ > + mmu_cr4_features = read_cr4(); > + } > + > #ifdef CONFIG_X86_32 > /* sync back kernel address range */ > clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY, Looks ok Acked-by: Stefan Bader <stefan.bader@canonical.com>
On 04/07/2011 02:15 PM, Herton Ronaldo Krzesinski wrote: > From: H. Peter Anvin <hpa@linux.intel.com> > > Restore the initialization of mmu_cr4_features during boot, which was > removed without comment in checkin e5f15b45ddf3afa2bbbb10c7ea34fb32b6de0a0e > > x86: Cleanup highmap after brk is concluded > > thereby breaking resume from hibernate. This restores previous > functionality in approximately the same place, and corrects the > reading of %cr4 on pre-CPUID hardware (%cr4 exists if and only if > CPUID is supported.) > > However, part of the problem is that the hibernate suspend/resume > sequence should manage the save/restore of %cr4 explicitly. > > Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> > Cc: Rafael J. Wysocki <rjw@sisk.pl> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: Yinghai Lu <yinghai@kernel.org> > LKML-Reference: <201104020154.57136.rjw@sisk.pl> > (cherry picked from commit 4da9484bdece39ab0b098fa711e095e3e9fc8684) > Tested-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> > BugLink: http://bugs.launchpad.net/bugs/752870 > Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> > --- > arch/x86/kernel/setup.c | 5 +++++ > 1 files changed, 5 insertions(+), 0 deletions(-) > > diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c > index e543fe9..4e59873 100644 > --- a/arch/x86/kernel/setup.c > +++ b/arch/x86/kernel/setup.c > @@ -1013,6 +1013,11 @@ void __init setup_arch(char **cmdline_p) > paging_init(); > x86_init.paging.pagetable_setup_done(swapper_pg_dir); > > + if (boot_cpu_data.cpuid_level >= 0) { > + /* A CPU has %cr4 if and only if it has CPUID */ > + mmu_cr4_features = read_cr4(); > + } > + > #ifdef CONFIG_X86_32 > /* sync back kernel address range */ > clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY, I tried to replicate this and test on my amd64 machine but it appears, hibernate is failing at an earlier point for me. The patch looks good though Acked-by: John Johansnen <john.johansen@canonical.com>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index e543fe9..4e59873 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1013,6 +1013,11 @@ void __init setup_arch(char **cmdline_p) paging_init(); x86_init.paging.pagetable_setup_done(swapper_pg_dir); + if (boot_cpu_data.cpuid_level >= 0) { + /* A CPU has %cr4 if and only if it has CPUID */ + mmu_cr4_features = read_cr4(); + } + #ifdef CONFIG_X86_32 /* sync back kernel address range */ clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY,