On Fri, Apr 19, 2024 at 10:55:44PM +0800, Mingzheng Xing wrote: > On 4/19/24 21:58, Greg Kroah-Hartman wrote: > > On Fri, Apr 19, 2024 at 08:26:07PM +0800, Mingzheng Xing wrote: > >> On 4/19/24 18:44, Greg Kroah-Hartman wrote: > >>> On Tue, Apr 16, 2024 at 04:56:47PM +0800, Mingzheng Xing wrote: > >>>> This reverts commit 1d6cd2146c2b58bc91266db1d5d6a5f9632e14c0 which has been > >>>> merged into the mainline commit 39365395046f ("riscv: kdump: use generic > >>>> interface to simplify crashkernel reservation"), but the latter's series of > >>>> patches are not included in the 6.6 branch. > >>>> > >>>> This will result in the loss of Crash kernel data in /proc/iomem, and kdump > >>>> loading the kernel will also cause an error: > >>>> > >>>> ``` > >>>> Memory for crashkernel is not reserved > >>>> Please reserve memory by passing"crashkernel=Y@X" parameter to kernel > >>>> Then try to loading kdump kernel > >>>> ``` > >>>> > >>>> After revert this patch, verify that it works properly on QEMU riscv. > >>>> > >>>> Link: https://lore.kernel.org/linux-riscv/ZSiQRDGLZk7lpakE@MiWiFi-R3L-srv > >>>> Signed-off-by: Mingzheng Xing <xingmingzheng@xxxxxxxxxxx> > >>>> --- > >>> > >>> I do not understand, what branch is this for? Why have you not cc:ed > >>> any of the original developers here? Why does Linus's tree not have the > >>> same problem? And the first sentence above does not make much sense as > >>> a 6.6 change is merged into 6.7? > >> > >> Sorry, I'll try to explain it more clearly. > >> > >> This commit 1d6cd2146c2b ("riscv: kdump: fix crashkernel reserving problem > >> on RISC-V") should not have existed because this patch has been merged into > >> another larger patch [1]. Here is that complete series: > > > > What "larger patch"? It is in Linus's tree, so it's not part of > > something different, right? I'm confused. > > > > Hi, Greg > > The email Cc:ed to author Chen Jiahao was bounced by the system, so maybe > we can wait for Baoquan He to confirm. > > This is indeed a bit confusing. The Fixes: tag in 1d6cd2146c2b58 is a false > reference. If I understand correctly, this is similar to the following > scenario: > > A Fixes B, B doesn't go into linus mainline. C contains A, C goes into linus > mainline 6.7, and C has more reconstruction code. but A goes into 6.6, so > it doesn't make sense for A to be in the mainline, and there's no C in 6.6 > but there's an A, thus resulting in an incomplete code that creates an error. > > The link I quoted [1] shows that Baoquan had expressed an opinion on this > at the time. > > Link: https://lore.kernel.org/linux-riscv/ZSiQRDGLZk7lpakE@MiWiFi-R3L-srv [1] I'm sorry, but I still do not understand what I need to do here for a stable branch. Do I need to apply something? Revert something? Something else? confused, greg k-h