| Message ID | 1443818865-19846-8-git-send-email-jeremy.linton@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Oct 02, 2015 at 03:47:45PM -0500, Jeremy Linton wrote: > These flags allow the user to enable/disable the contiguous PTE > detection and marking on the kernel command line for > debugging purposes. > > Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> > --- > Documentation/kernel-parameters.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 22a4b68..2766290 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -744,6 +744,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > seconds. Defaults to 10*60 = 10mins. A value of 0 > disables the blank timer. > > + contpte [ARM64] Enable contiguous PTE marking for the kernel > + linear range. This may be disabled with nocontpte. > + Default: Enabled I recall you asked the question but I didn't have the time to reply. I don't think we need a command line option for this. In the "unlikely" event that something is broken in hardware (or software) and we want to disable the contiguous bit, I would rather have a Kconfig option.
On 10/05/2015 11:49 AM, Catalin Marinas wrote: > I recall you asked the question but I didn't have the time to reply. I > don't think we need a command line option for this. In the "unlikely" > event that something is broken in hardware (or software) and we want to > disable the contiguous bit, I would rather have a Kconfig option. How about both? Other users of early_param_on_off() set the default state using kconfig. Is that an acceptable choice, or should I remove the command line parameter all together? I sort of expect that in a few years time, the whole option goes away once it been in use for a while and there are a number of V8 implementations widely available.
On Mon, Oct 05, 2015 at 01:29:55PM -0500, Jeremy Linton wrote: > On 10/05/2015 11:49 AM, Catalin Marinas wrote: > >I recall you asked the question but I didn't have the time to reply. I > >don't think we need a command line option for this. In the "unlikely" > >event that something is broken in hardware (or software) and we want to > >disable the contiguous bit, I would rather have a Kconfig option. > > How about both? Other users of early_param_on_off() set the default state > using kconfig. Is that an acceptable choice, or should I remove the command > line parameter all together? I sort of expect that in a few years time, the > whole option goes away once it been in use for a while and there are a > number of V8 implementations widely available. If for debugging purposes we could get away with just changing PAGE_KERNEL_EXEC_CONT, I think we can avoid both command line and Kconfig option. Otherwise only a Kconfig option, I don't see much point in a command line option (maybe benchmarking).
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 22a4b68..2766290 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -744,6 +744,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. seconds. Defaults to 10*60 = 10mins. A value of 0 disables the blank timer. + contpte [ARM64] Enable contiguous PTE marking for the kernel + linear range. This may be disabled with nocontpte. + Default: Enabled + coredump_filter= [KNL] Change the default value for /proc/<pid>/coredump_filter.
These flags allow the user to enable/disable the contiguous PTE detection and marking on the kernel command line for debugging purposes. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> --- Documentation/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+)