On 11/11/19 at 01:31pm, Bhupesh Sharma wrote: > Changes since v3: > ---------------- > - v3 can be seen here: > http://lists.infradead.org/pipermail/kexec/2019-March/022590.html > - Addressed comments from James and exported TCR_EL1.T1SZ in vmcoreinfo > instead of PTRS_PER_PGD. > - Added a new patch (via [PATCH 3/3]), which fixes a simple typo in > 'Documentation/arm64/memory.rst' > > Changes since v2: > ---------------- > - v2 can be seen here: > http://lists.infradead.org/pipermail/kexec/2019-March/022531.html > - Protected 'MAX_PHYSMEM_BITS' vmcoreinfo variable under CONFIG_SPARSEMEM > ifdef sections, as suggested by Kazu. > - Updated vmcoreinfo documentation to add description about > 'MAX_PHYSMEM_BITS' variable (via [PATCH 3/3]). > > Changes since v1: > ---------------- > - v1 was sent out as a single patch which can be seen here: > http://lists.infradead.org/pipermail/kexec/2019-February/022411.html > > - v2 breaks the single patch into two independent patches: > [PATCH 1/2] appends 'PTRS_PER_PGD' to vmcoreinfo for arm64 arch, whereas > [PATCH 2/2] appends 'MAX_PHYSMEM_BITS' to vmcoreinfo in core kernel code > (all archs) > > This patchset primarily fixes the regression reported in user-space > utilities like 'makedumpfile' and 'crash-utility' on arm64 architecture > with the availability of 52-bit address space feature in underlying > kernel. These regressions have been reported both on CPUs which don't > support ARMv8.2 extensions (i.e. LVA, LPA) and are running newer kernels > and also on prototype platforms (like ARMv8 FVP simulator model) which > support ARMv8.2 extensions and are running newer kernels. > > The reason for these regressions is that right now user-space tools > have no direct access to these values (since these are not exported > from the kernel) and hence need to rely on a best-guess method of > determining value of 'vabits_actual' and 'MAX_PHYSMEM_BITS' supported > by underlying kernel. > > Exporting these values via vmcoreinfo will help user-land in such cases. > In addition, as per suggestion from makedumpfile maintainer (Kazu), > it makes more sense to append 'MAX_PHYSMEM_BITS' to > vmcoreinfo in the core code itself rather than in arm64 arch-specific > code, so that the user-space code for other archs can also benefit from > this addition to the vmcoreinfo and use it as a standard way of > determining 'SECTIONS_SHIFT' value in user-land. > > Cc: Boris Petkov <b...@alien8.de> > Cc: Ingo Molnar <mi...@kernel.org> > Cc: Thomas Gleixner <t...@linutronix.de> > Cc: Jonathan Corbet <cor...@lwn.net> > Cc: James Morse <james.mo...@arm.com> > Cc: Mark Rutland <mark.rutl...@arm.com> > Cc: Will Deacon <w...@kernel.org> > Cc: Steve Capper <steve.cap...@arm.com> > Cc: Catalin Marinas <catalin.mari...@arm.com> > Cc: Ard Biesheuvel <ard.biesheu...@linaro.org> > Cc: Michael Ellerman <m...@ellerman.id.au> > Cc: Paul Mackerras <pau...@samba.org> > Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> > Cc: Dave Anderson <ander...@redhat.com> > Cc: Kazuhito Hagio <k-ha...@ab.jp.nec.com> > Cc: x...@kernel.org > Cc: linuxppc-dev@lists.ozlabs.org > Cc: linux-arm-ker...@lists.infradead.org > Cc: linux-ker...@vger.kernel.org > Cc: linux-...@vger.kernel.org > Cc: ke...@lists.infradead.org > > Bhupesh Sharma (3): > crash_core, vmcoreinfo: Append 'MAX_PHYSMEM_BITS' to vmcoreinfo > arm64/crash_core: Export TCR_EL1.T1SZ in vmcoreinfo
Soft reminder: the new introduced vmcoreinfo needs documentation Please check Documentation/admin-guide/kdump/vmcoreinfo.rst Thanks Dave