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Peter Anvin" , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonas Bonn , Stefan Kristiansson , Stafford Horne Cc: 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, Yeoreum Yun X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3423; i=yeoreum.yun@arm.com; h=from:subject:message-id; bh=wn+xbNqkdezctD1uOfR77s9+bFTC1HhX6zz+en43LNA=; b=owEB7QES/pANAwAKAW3Vw9FaxTEzAcsmYgBqsQ1UuhWv4I3FDWdg/j+kldAjB8reMz42JzLq7 0YDZbKbMleJAbMEAAEKAB0WIQQtg+CS3QUzuFh1pJ1t1cPRWsUxMwUCarENVAAKCRBt1cPRWsUx M6vtDACSfqly9thwjD7kl8mtPM+GTHEk5P3hm5m3IcHM/yuady/yC8uUCYqEGqoqo0+xVZg5dgc DittGiSonPPEQke2O5H2aGKT7mRrcR7TcXtn312UQhs/CXyL6IytQkZSPwYBo+4XndAU67RxoqN Cbsb2z1qPHth4uMqDPK0ebT4y8OryhIDkXSGTvJPERdR6MDhQVkGseyybG2Mk2Ba9mBzPj+/EOe M61uV5vI5bCjaQGTix6ZM+pGrQfDWmTcNYaiK88gLoLnHbs2067hK4HrTuFOSYvs+elrKeXkg6X +eGlZclNAyJaHSTztQxSdmDlcYZMkFDaIbj3QcEmslWhN2UJGwcz23nYG4e4X4Z0TSSGKhoFWM4 508raZYgajEUFud/R93/AmlmYmuBoZ2zSp+pZtkt7f2JgxqjyQ0/oDk7EsKaVz8Nf3HQCxEIu7A GuAMHSv7/yJ6SXa9h7ifoRm+G9lXvGUSHQEFgv689N84mIZhD8joOcXHWX0dJvUOyz0WU= X-Developer-Key: i=yeoreum.yun@arm.com; a=openpgp; fpr=2D83E092DD0533B85875A49D6DD5C3D15AC53133 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: A834E4000A X-Stat-Signature: tknpnbhhtwuaydqfyghidhz711tbga5d X-Rspam-User: X-HE-Tag: 1789988340-531144 X-HE-Meta: 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 Qg4UDil9 MIKbTxSexD65f5wWntNw2uYc2OOxfIyGP4Cn7lHbcsks0lDxE+/UQCx8XZkfvlYBmQoqMWpXEuxJRCqii37iLh2JonlCenhNsj4PHI9S8Fko+vI5TUeL14o1pBIyughsELw1NQjg//kLnMIp8z6s0EqvVL0gHcnjonIDTTwrDUwyE3fdAAGPDev+nDpFN6xxDz4alC3gPoAWls6UVyJsttV31a1mnFi2b84BJc+XUvOBJ+cngbXxuMCe6ujPzXrDoXCFfMU6/JnDAe3V//PYwkCUnAmWelIWnEDSq1kPFaROJknQnWoZQcPE0S+8Um9qftDU5biyd263W0/M= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: "David Hildenbrand (Arm)" pXdp_get() could return a dummy value for a page-table level folded at compile time. Passing this value to set_pXd() could cause unexpected behavior. Prevent this at compile time by ensuring that all calls to set_pgd()/set_p4d()/set_pud() are compiled out for folded page-table levels. Make the compiler complain if these helpers are called with dummy values. Since there are places where set_pXd() is called even when the corresponding page-table level is folded at compile time, drop the incorrect comments for set_pXd(). Signed-off-by: David Hildenbrand (Arm) Co-developed-by: Yeoreum Yun Signed-off-by: Yeoreum Yun --- include/asm-generic/pgtable-nop4d.h | 11 ++++++----- include/asm-generic/pgtable-nopmd.h | 10 +++++----- include/asm-generic/pgtable-nopud.h | 12 +++++++----- 3 files changed, 18 insertions(+), 15 deletions(-) diff --git a/include/asm-generic/pgtable-nop4d.h b/include/asm-generic/pgtable-nop4d.h index d2dccf7542da5..12b01768134b5 100644 --- a/include/asm-generic/pgtable-nop4d.h +++ b/include/asm-generic/pgtable-nop4d.h @@ -28,11 +28,12 @@ static inline bool pgd_leaf(pgd_t pgd) { return false; } #define pgd_populate(mm, pgd, p4d) do { } while (0) #define pgd_populate_safe(mm, pgd, p4d) do { } while (0) -/* - * (p4ds are folded into pgds so this doesn't get actually called, - * but the define is needed for a generic inline function.) - */ -#define set_pgd(pgdptr, pgdval) set_p4d((p4d_t *)(pgdptr), (p4d_t) { pgdval }) + +#define set_pgd(pgdptr, pgdval) \ +({ \ + pgd_check_dummy(pgdval); \ + set_p4d((p4d_t *)(pgdptr), (p4d_t) { pgdval }); \ +}) static __always_inline pgd_t pgdp_get(pgd_t *pgdp) { diff --git a/include/asm-generic/pgtable-nopmd.h b/include/asm-generic/pgtable-nopmd.h index 2afbf2d8659dc..11b04c1071295 100644 --- a/include/asm-generic/pgtable-nopmd.h +++ b/include/asm-generic/pgtable-nopmd.h @@ -37,11 +37,11 @@ static inline void pud_clear(pud_t *pud) { } #define pud_populate(mm, pmd, pte) do { } while (0) -/* - * (pmds are folded into puds so this doesn't get actually called, - * but the define is needed for a generic inline function.) - */ -#define set_pud(pudptr, pudval) set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval }) +#define set_pud(pudptr, pudval) \ +({ \ + pud_check_dummy(pudval); \ + set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval }); \ +}) static __always_inline pud_t pudp_get(pud_t *pudp) { diff --git a/include/asm-generic/pgtable-nopud.h b/include/asm-generic/pgtable-nopud.h index 3264673c0c386..5ee8f1852cd8c 100644 --- a/include/asm-generic/pgtable-nopud.h +++ b/include/asm-generic/pgtable-nopud.h @@ -35,11 +35,13 @@ static inline bool p4d_leaf(p4d_t p4d) { return false; } #define p4d_populate(mm, p4d, pud) do { } while (0) #define p4d_populate_safe(mm, p4d, pud) do { } while (0) -/* - * (puds are folded into p4ds so this doesn't get actually called, - * but the define is needed for a generic inline function.) - */ -#define set_p4d(p4dptr, p4dval) set_pud((pud_t *)(p4dptr), (pud_t) { p4dval }) + +#define set_p4d(p4dptr, p4dval) \ +({ \ + p4d_check_dummy(p4dval); \ + set_pud((pud_t *)(p4dptr), (pud_t) { p4dval }); \ +}) + static __always_inline p4d_t p4dp_get(p4d_t *p4dp) { -- 2.43.0