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Peter Anvin" , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonas Bonn , Stefan Kristiansson , Stafford Horne , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-openrisc@vger.kernel.org Subject: Re: [PATCH 21/21] Documentation: mm: clarify behaviour of compile-time folded page tables Message-ID: References: <20260921-dummy_ptxp3-v1-0-cd40cf68242e@arm.com> <20260921-dummy_ptxp3-v1-21-cd40cf68242e@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: B215B1C0003 X-Stat-Signature: 4m835oozne5mkewrxkri3n1qzkahu6js X-Rspam-User: X-HE-Tag: 1790022410-763838 X-HE-Meta: U2FsdGVkX1/sEuLvlL/qd7mUZUwXh+jOsJWzXYptyw9DAQ/p13abld64d2VfzyOX4FDKiFbyFqN9C48Wz5oazxV3AKFAG9rnnQRFlz8ubJ97k9fy9ClGu/m3VdXHu0kbXBgPdhst29WcLEgrEl93nBn/M/RaQc9ycaioIKRHqhO+oSe8KPOVCIJIUDdPQUv3g246aN7zB5v9k2nrydjp9MoQ7H1siero9s3gz/nmmVCPt4ciNf6r5rBG90VtC9KMwS75g22w9X9J16kHq+1TNWZeahtYamLNCFB5Y1c+79gNK9kijqTDNOCG6maxMJug9c7HPRMJ+lGPqpS+m/cQiMk7rHUUURIZPg+1KE8qP7fnA3VQlZodbCwu9rVpHAFADJPKCTo2+J4ShcpkvHF/MPTFS7eqKdxhRlfM4PrxISfpKcL6vSqOoxJgHl/+1JL6ZdV/QUunl1OLLozFJKkUCB/eDsHu43Msoj5cabs8/gEbUVoRaZNIiJZX4ZC7m2I7JYLPuSghjHYjDPFArgct+o8f/5iCYnV5dtXLoMsPC4Cp4Ku804SIJWXlzuiC287GdN8BCg06EpoaWk0Zbr3VdOGbFjI6FtckRs4JX56Z1tYL0ZlesuAezYObBo2m/khBMKGG80sqoMqRJh7/e+S+h6DxJoSyZui52Qhgrivpta8L46DTwdmDJfiydwEoEnxgkVBobHz1Ieq1XGeqrnKi6WgVNiLvgtwxHK7iOoD2GwpTcUYmUDwH+NnUJxQT1vuEo1WGzDJjKqHo2Ze27hJHDi+xZEE8qWYc4BtpwD3ArtB0pJrnagtugS1O10aeV2EYhLX7VT9aWsg9jm44Kt+fXHR2q98EabVfTDSagu5l4ymmQo1WGOBDN3/RNaG/QoZoCJUaZX/ou05kgPQ9870T7Xjao3HIjs5oG4ar4/cIxbL6NS/jP9Kl5V8Qb+SiORjfBNv1p/b9aut8oLhrqKA P/rF72Ol aBrTTo84fI0NddaW7b2y4i+k5u6dDPucvfSAcMMh3N5pTO6flsv9HKXsMr9jqBEy3L9giDsNHPt6OX7KYs+H04+IQQpOCgtGx9iHHIv+hpw75+RO6RirIZL1mrKRwA1ux4ttu8nSV/VbzieKuLrFroNjHTUnZ1C2rvRBSosWdOY0519s1JOkG8sSj0J+rMrJ5IFRI1hS6cGyjh1o6AoqMgc/fz9Ue6qjq0RMJq2Q+HlB+YxMbV25Z8+ZVuRSwjn9wL/zF Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Randy, > > > On 9/21/26 3:55 AM, Yeoreum Yun wrote: > > From: "David Hildenbrand (Arm)" > > > > Compile-time folded page tables are not necessarily easy to understand, and even > > people the were once familiar with the concept might need to refresh their memory. > > > > Add proper documentation, including a nice diagram, for the current design. > > Mention details about dummy functions, including the recently changed pXdp_get() > > helpers. > > > > Signed-off-by: David Hildenbrand (Arm) > > Documentation/mm/page_tables.rst:197: WARNING: Bullet list ends without a blank line; unexpected unindent. [docutils] > > See below for a fix. [...] > > +Note that the arrows from PGD to NOP4D represent page-table-walker > > +transitions, not pointers stored in the pgd entries. > > + > > +Using p4d as an example, `nop4d`/`p4d folded` translates to the following: > > + > > +- p4d is considered folded into pgd; both are operating on the same page > > + table. > > table. > (add one more prefix space to align the indentation) > Thanks! I'll fix it! [...] -- Sincerely, Yeoreum Yun