| Message ID | 20190507035058.63992-5-chenzhou10@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | support reserving crashkernel above 4G on arm64 kdump | expand |
On 05/07/2019 09:20 AM, Chen Zhou wrote: > Now we support crashkernel=X,[high,low] on arm64, update the > Documentation. > > Signed-off-by: Chen Zhou <chenzhou10@huawei.com> > --- > Documentation/admin-guide/kernel-parameters.txt | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 268b10a..03a08aa 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -705,7 +705,7 @@ > memory region [offset, offset + size] for that kernel > image. If '@offset' is omitted, then a suitable offset > is selected automatically. > - [KNL, x86_64] select a region under 4G first, and > + [KNL, x86_64, arm64] select a region under 4G first, and > fall back to reserve region above 4G when '@offset' > hasn't been specified. > See Documentation/kdump/kdump.txt for further details. > @@ -718,14 +718,14 @@ > Documentation/kdump/kdump.txt for an example. > > crashkernel=size[KMG],high > - [KNL, x86_64] range could be above 4G. Allow kernel > + [KNL, x86_64, arm64] range could be above 4G. Allow kernel > to allocate physical memory region from top, so could > be above 4G if system have more than 4G ram installed. > Otherwise memory region will be allocated below 4G, if > available. > It will be ignored if crashkernel=X is specified. > crashkernel=size[KMG],low > - [KNL, x86_64] range under 4G. When crashkernel=X,high > + [KNL, x86_64, arm64] range under 4G. When crashkernel=X,high > is passed, kernel could allocate physical memory region > above 4G, that cause second kernel crash on system > that require some amount of low memory, e.g. swiotlb > IMO, it is a good time to update 'Documentation/kdump/kdump.txt' with this patchset itself for both x86_64 and arm64, where we still specify only the old format for 'crashkernel' boot-argument: Section: Boot into System Kernel ======================= On arm64, use "crashkernel=Y[@X]". Note that the start address of the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). ... We can update this to add the new crashkernel=size[KMG],low or crashkernel=size[KMG],high format as well. Thanks, Bhupesh
On 2019/5/15 13:16, Bhupesh Sharma wrote: > On 05/07/2019 09:20 AM, Chen Zhou wrote: >> Now we support crashkernel=X,[high,low] on arm64, update the >> Documentation. >> >> Signed-off-by: Chen Zhou <chenzhou10@huawei.com> >> --- >> Documentation/admin-guide/kernel-parameters.txt | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >> index 268b10a..03a08aa 100644 >> --- a/Documentation/admin-guide/kernel-parameters.txt >> +++ b/Documentation/admin-guide/kernel-parameters.txt >> @@ -705,7 +705,7 @@ >> memory region [offset, offset + size] for that kernel >> image. If '@offset' is omitted, then a suitable offset >> is selected automatically. >> - [KNL, x86_64] select a region under 4G first, and >> + [KNL, x86_64, arm64] select a region under 4G first, and >> fall back to reserve region above 4G when '@offset' >> hasn't been specified. >> See Documentation/kdump/kdump.txt for further details. >> @@ -718,14 +718,14 @@ >> Documentation/kdump/kdump.txt for an example. >> crashkernel=size[KMG],high >> - [KNL, x86_64] range could be above 4G. Allow kernel >> + [KNL, x86_64, arm64] range could be above 4G. Allow kernel >> to allocate physical memory region from top, so could >> be above 4G if system have more than 4G ram installed. >> Otherwise memory region will be allocated below 4G, if >> available. >> It will be ignored if crashkernel=X is specified. >> crashkernel=size[KMG],low >> - [KNL, x86_64] range under 4G. When crashkernel=X,high >> + [KNL, x86_64, arm64] range under 4G. When crashkernel=X,high >> is passed, kernel could allocate physical memory region >> above 4G, that cause second kernel crash on system >> that require some amount of low memory, e.g. swiotlb >> > > IMO, it is a good time to update 'Documentation/kdump/kdump.txt' with this patchset itself for both x86_64 and arm64, where we still specify only the old format for 'crashkernel' boot-argument: > > Section: Boot into System Kernel > ======================= > > On arm64, use "crashkernel=Y[@X]". Note that the start address of > the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > ... > > We can update this to add the new crashkernel=size[KMG],low or crashkernel=size[KMG],high format as well. > > Thanks, > Bhupesh > > . Sure, we can also update here. Thanks, Chen Zhou
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 268b10a..03a08aa 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -705,7 +705,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, x86_64] select a region under 4G first, and + [KNL, x86_64, arm64] select a region under 4G first, and fall back to reserve region above 4G when '@offset' hasn't been specified. See Documentation/kdump/kdump.txt for further details. @@ -718,14 +718,14 @@ Documentation/kdump/kdump.txt for an example. crashkernel=size[KMG],high - [KNL, x86_64] range could be above 4G. Allow kernel + [KNL, x86_64, arm64] range could be above 4G. Allow kernel to allocate physical memory region from top, so could be above 4G if system have more than 4G ram installed. Otherwise memory region will be allocated below 4G, if available. It will be ignored if crashkernel=X is specified. crashkernel=size[KMG],low - [KNL, x86_64] range under 4G. When crashkernel=X,high + [KNL, x86_64, arm64] range under 4G. When crashkernel=X,high is passed, kernel could allocate physical memory region above 4G, that cause second kernel crash on system that require some amount of low memory, e.g. swiotlb
Now we support crashkernel=X,[high,low] on arm64, update the Documentation. Signed-off-by: Chen Zhou <chenzhou10@huawei.com> --- Documentation/admin-guide/kernel-parameters.txt | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)