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V" , Linux Kernel Mailing List , Nick Piggin , Linux-MM , Andrew Morton , linux-snps-arc@lists.infradead.org, Will Deacon , "Kirill A . Shutemov" References: <20191011121951.nxna6hruuskvdxod@box> <20191011223818.7238-1-vgupta@synopsys.com> From: Vineet Gupta Openpgp: preference=signencrypt Autocrypt: addr=vineetg76@gmail.com; prefer-encrypt=mutual; keydata= mQINBFEffBMBEADIXSn0fEQcM8GPYFZyvBrY8456hGplRnLLFimPi/BBGFA24IR+B/Vh/EFk B5LAyKuPEEbR3WSVB1x7TovwEErPWKmhHFbyugdCKDv7qWVj7pOB+vqycTG3i16eixB69row lDkZ2RQyy1i/wOtHt8Kr69V9aMOIVIlBNjx5vNOjxfOLux3C0SRl1veA8sdkoSACY3McOqJ8 zR8q1mZDRHCfz+aNxgmVIVFN2JY29zBNOeCzNL1b6ndjU73whH/1hd9YMx2Sp149T8MBpkuQ cFYUPYm8Mn0dQ5PHAide+D3iKCHMupX0ux1Y6g7Ym9jhVtxq3OdUI5I5vsED7NgV9c8++baM 7j7ext5v0l8UeulHfj4LglTaJIvwbUrCGgtyS9haKlUHbmey/af1j0sTrGxZs1ky1cTX7yeF nSYs12GRiVZkh/Pf3nRLkjV+kH++ZtR1GZLqwamiYZhAHjo1Vzyl50JT9EuX07/XTyq/Bx6E dcJWr79ZphJ+mR2HrMdvZo3VSpXEgjROpYlD4GKUApFxW6RrZkvMzuR2bqi48FThXKhFXJBd JiTfiO8tpXaHg/yh/V9vNQqdu7KmZIuZ0EdeZHoXe+8lxoNyQPcPSj7LcmE6gONJR8ZqAzyk F5voeRIy005ZmJJ3VOH3Gw6Gz49LVy7Kz72yo1IPHZJNpSV5xwARAQABtC1WaW5lZXQgR3Vw dGEgKHBlcnNvbmFsKSA8dmluZWV0Zzc2QGdtYWlsLmNvbT6JAj4EEwECACgCGwMGCwkIBwMC BhUIAgkKCwQWAgMBAh4BAheABQJdcAXyBQkVtotfAAoJEGnX8d3iisJeH6EP/ip0xGS2DNI4 2za/eRU85Kc+wQhz/NWhDMCl3xWzKLBO4SaOMlfp7j4vgogj7ufok7I7Ke0Tvww9kbk+vgeg ERlcGd+OczDX4ze4EabgW5z8sMax84yqd/4HVJBORGtjR5uXh0fugKrTBGA5AJMf/qGyyHZX 8vemIm7gQK7aUgkKId9D4O1wIdgrUdvg8ocFw9a1TWv6s3keyJNfqKKwSNdywKbVdkMFjLcL d6jHP9ice59Fkh4Lhte6DfDx4gjbhF1gyoqSL/JvaBLYJTdkl2tGzM/CYSqOsivUH9//X5uT ijG3mkIqb//7H1ab/zgF0/9jxjhtiKYwl71NN9Zm2rJiGegLxv61RjEZT2oEacZXIyXqZSh/ vz8rWOBAr1EE76XzqC5TC6qa5Xdo2Q9g5d9p7pkQ9WFfDAQujrB8qZIS6IwhFPSZQIGUWB5x F/CskhsxXOgPL0isSv6a5OB2jd3G78/o7GfDSaiOVzgL4hx4gIY0aQqANuNlLC8q55fYquMS lO4FqcpaK5yt81uzPTv8HetA1577Yeur9aPjgZpqHI35f6V7uQdDRQlI8kmkm/ceWAxbliR3 YjH32HRGpOc6Z3q1gGSruPnpjeSRVjb8GJGEIWLbhcyF/kRV6T6vcER3x4LaBnmU17uE5vw4 789n0dLVksMviHzcGg1/8WUvuQINBFEffBMBEADXZ2pWw4Regpfw+V+Vr6tvZFRl245PV9rW FU72xNuvZKq/WE3xMu+ZE7l2JKpSjrEoeOHejtT0cILeQ/Yhf2t2xAlrBLlGOMmMYKK/K0Dc 2zf0MiPRbW/NCivMbGRZdhAAMx1bpVhInKjU/6/4mT7gcE57Ep0tl3HBfpxCK8RRlZc3v8BH OaEfcWSQD7QNTZK/kYJo+Oyux+fzyM5TTuKAaVE63NHCgWtFglH2vt2IyJ1XoPkAMueLXay6 enSKNci7qAG2UwicyVDCK9AtEub+ps8NakkeqdSkDRp5tQldJbfDaMXuWxJuPjfSojHIAbFq P6QaANXvTCSuBgkmGZ58skeNopasrJA4z7OsKRUBvAnharU82HGemtIa4Z83zotOGNdaBBOH NN2MHyfGLm+kEoccQheH+my8GtbH1a8eRBtxlk4c02ONkq1Vg1EbIzvgi4a56SrENFx4+4sZ cm8oItShAoKGIE/UCkj/jPlWqOcM/QIqJ2bR8hjBny83ONRf2O9nJuEYw9vZAPFViPwWG8tZ 7J+ReuXKai4DDr+8oFOi/40mIDe/Bat3ftyd+94Z1RxDCngd3Q85bw13t2ttNLw5eHufLIpo EyAhTCLNQ58eT91YGVGvFs39IuH0b8ovVvdkKGInCT59Vr0MtfgcsqpDxWQXJXYZYTFHd3/R swARAQABiQIlBBgBAgAPAhsMBQJdcAYOBQkVtot7AAoJEGnX8d3iisJeCGAP/0QNMvc0QfIq z7CzZWSai8s74YxxzNRwTigxgx0YjHFYWDd6sYYdhqFSjeQ6p//QB5Uu+5YByzM2nHiDH0ys cL0iTZIz3IEq/IL65SNShdpUrzD3mB/gS95IYxBcicRXXFA7gdYDYmX86fjqJO2dCAhdO2l/ BHSi6KOaM6BofxwQz5189/NsxuF03JplqLgUgkpKWYJxkx9+CsQL+gruDc1iS9BFJ6xoXosS 2ieZYflNGvslk1pyePM7miK5BaMZcpvJ/i50rQBUEnYi0jGeXxgbMSuLy/KiNLcmkKucaRO+ h2g0nxEADaPezfg5yBrUYCvJy+dIO5y2wS80ayO16yxkknlN1y4GuLVSj4vmJWiT6DENPWmO fQADBBcHsexVV8/CjCkzfYiXPC7dMAT7OZE+nXSZJHQiCR0LUSToICFZ+Pntj1bjMLu9mDSy AtnheBEXom1b7TTHOZ13HuU4Cue9iNoACjVbbF9Zg4+YRmvtcPy8tTo5DXBdysrF7sO/yWGu ukgWa2otyae8BC7qBYFbm6uk9wMbYSN3yYBmbiAULMrBKA33iWlE0rIKMv91a2DVjp4NiOSu gyyFD9n83Sn4lcyjdLvBUCn9zgY4TwufG/ozyF2hSmO3iIzqt0GxmpQ+pBXk/m51D/UoTWGl deE0Dvw98SWmZSNtdOPnJZ0D Message-ID: Date: Mon, 14 Oct 2019 11:02:38 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 10/14/19 10:41 AM, Linus Torvalds wrote: > On Fri, Oct 11, 2019 at 3:38 PM Vineet Gupta wrote: >> >> This is inine with similar patches for nopud [1] and nop4d [2] cases. > > I don't think your patch is wrong, but wouldn't it be easier and > cleaner to just do this instead > > --- a/include/asm-generic/pgtable-nopmd.h > +++ b/include/asm-generic/pgtable-nopmd.h > @@ -60,7 +60,7 @@ static inline pmd_t * pmd_offset(pud_t * pud, > unsigned long address) > static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd) > { > } > -#define __pmd_free_tlb(tlb, x, a) do { } while (0) > +#define pmd_free_tlb(tlb, x, a) do { } while (0) > > #undef pmd_addr_end > #define pmd_addr_end(addr, end) (end) I suppose we could but (a) It would be asymmetric with the __p{u,4}d_free_tlb() changes in [1] and [2]. Do you prefer [1] and [2] be repun along the same lines as you propose above ? (b) IMHO p?d_free_tlb() under corresponding #ifndef *P?D_FOLDED is much clearer to read as being stubbed out. But this is minor point. Also would you care to shed light on my other question about not being able to fold away pmd_clear_bad() despite PMD_FOLDED given the pmd macros actually checking for pgd. Of all the people you are likely to have most insight on how the pmd folding actually evolved and works :-) Thx, -Vineet [1] http://lists.infradead.org/pipermail/linux-snps-arc/2019-October/006266.html [2] http://lists.infradead.org/pipermail/linux-snps-arc/2019-October/006265.html