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Howlett" , linux-kernel@vger.kernel.org, willy@infradead.org, linux-mm@kvack.org, mcgrof@kernel.org, gost.dev@samsung.com, Pankaj Raghav References: <20250904095129.222316-1-kernel@pankajraghav.com> <2psecfvsd4lbgcm6aflifi2kc6gof345txsvk7wtsytre5ehqt@4wyru36aaeel> Content-Language: en-US From: Pankaj Raghav In-Reply-To: <2psecfvsd4lbgcm6aflifi2kc6gof345txsvk7wtsytre5ehqt@4wyru36aaeel> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: CDF588000B X-Rspamd-Server: rspam04 X-Rspam-User: X-Stat-Signature: qk38u818iqbex8r3w8bo7xn6i75ntoy4 X-HE-Tag: 1757059998-731536 X-HE-Meta: U2FsdGVkX1+M6HElv/GEG05Gh37ziuqU2UKLu8a3OU5FjuKI26WgLuk7lE4EdznazfM3zn5w/f4q5Sadg1uTHNJ1rHMx2zgQO8gegO8vveFlmpACn9abZ2CcKggncE5JC+B/sBHsPpALgqzKENzUIpBUhXnQG3DoHFu6IaTcW7JfDe7HSOR3Hz3oDvzZAeab9pBHaEqQ5JvNGLQdXfau3JUkNKQIc2HGwXg3k/w/FiXhak/vGGFgqYpuw0rugdVWOXRJgvE5o9aiozdXiSilcuMjKMT8L7r9e2bnI2w+hytqQn4Lua918XPNMHlLdpgIy8Q6ZgbotC9jhm7dmOT515BmNh1V2kL9HC6uYz6u4+X4t1mLvvxIUaISrjTy6rVxiEWTjRYmHwE6P3PH678R2sTHokHuzuVzcbPGP6IZweGhBecTGi+a4kUfPWV19QJdG8Z5Hx8OXFSI6WesSQ/njJlWeMivy06RYdfJCIhsPes6VtCmOzOQKTvq0l3xtVdDOrapvZSOJdMBZ9WuDUXl+/KyBKlSuDqKbf1CdjxlO34qlVvl/hsl5oEDWZ7YGOLp1urvDXzXeNNVNReYtUio48sRcwxIuz1T0B8RmZNExskb+sy1DbH2WpTRV6L7vlZF8FlQatnoYUUJZs05LUFiZwmNHNwU+4zYtC+FueO4y4Mr2OOt2dK8qe6PC7NHD0HCLeXRIVXrbb6ClBd8ozfUhRj2RlOe2ZuZTGHQHX3usToegE4WgTxreulOK9l4PfBawVcuyfmjPuH2EJEBJoE1f6wlcPFvSPiyi5FBdE+Ry3hgiLYIEwjNAwnaNWwWorAU43iOXRo+6ytAldish+JLmEM38ubEaOqUruSptFNjEgNYWPeTkMslL/soyQHev4Y7tii8SMF0184G0F9DPehchYNGMFXkPw5z0l+nUZUjU8ZeX7xj8Zh+vMR7Y60RsWc66nR9YBZm72JAwgQwiBy G6LBayJM x9QOyZdwq0e6oblZtYzXENLv0+9mUL0toFL16liDxSC7+Rm/9nLATy9QmYC/LXWkFwbywkaiTcmJDmNCs4DzQrKIzCq9Uuwd8dPbtC1OwZ5QCkYcdXqHvcne21CfAA0Voi9cBhjMNHUKfTOtxSeav/EhrJRJC/Rlh0H1g3lHc+XGIbQQCntSfDg3ismZohjenwsdq5WCm+R8ILAitv7QCPCwfvLvuadD6aVwRgOc02Xd4YZexFDrHETNY8oX4JkFQIdzwwjVYmGN+hS33v7D8QmmUH464r7VF1+pFkAeXhmJApjJ80iKM69FB/8qqCtZ90oET5Z3PJKIzkSMlZXz1Ad/hrtk3+MnFjKvyf6o977mNKOzRO/gWupI2lzaBg9XGgJjz5fZzNwOWg20= 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: List-Subscribe: List-Unsubscribe: On 9/4/25 17:26, Kiryl Shutsemau wrote: > On Thu, Sep 04, 2025 at 11:51:29AM +0200, Pankaj Raghav (Samsung) wrote: >> From: Pankaj Raghav >> >> split_huge_page_to_list_[to_order](), split_huge_page() and >> try_folio_split() return 0 on success and error codes on failure. >> >> When THP is disabled, these functions return 0 indicating success even >> though an error code should be returned as it is not possible to split a >> folio when THP is disabled. >> >> Make all these functions return -EINVAL to indicate failure instead of >> 0. As large folios depend on CONFIG_THP, issue warning as this function >> should not be called without a large folio. >> >> Signed-off-by: Pankaj Raghav > > Acked-by: Kiryl Shutsemau > > Just curious, did you give BUILD_BUG() a try? > Yes, I tried BUILD_BUG() but it actually fails the build because truncate_inode_partial_folio() calls try_folio_split(). It won't be called in runtime because there is a check for large folios before we call this function. So a runtime warning is better in this case. -- Pankaj