[PATCH v3 0/2] vdso: Use only headers from the vdso/ namespace

[PATCH v3 0/2] vdso: Use only headers from the vdso/ namespace

[Vincenzo Frascino]

The recent implementation of getrandom in the generic vdso library,
includes headers from outside of the vdso/ namespace.

The purpose of this patch series is to refactor the code to make sure
that the library uses only the allowed namespace.

The series has been rebased on [1] to simplify the testing. 

[1] git://git.kernel.org/pub/scm/linux/kernel/git/crng/random.git master

Changes:
--------
v3:
  - Discard vdso/mman.h changes in favor of [2].
  - Refactor vdso/page.h.
  - Add a fix to drm/intel_gt.
v2:
  - Added common PAGE_SIZE and PAGE_MASK definitions.
  - Added opencoded macros where not defined.
  - Dropped VDSO_PAGE_* redefinitions.

[2] https://lore.kernel.org/lkml/20240925210615.2572360-1-arnd@kernel.org

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Naveen N Rao <naveen@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>

Vincenzo Frascino (2):
  drm: Fix fault format
  vdso: Introduce vdso/page.h

 arch/alpha/include/asm/page.h      |  6 +-----
 arch/arc/include/uapi/asm/page.h   |  7 +++----
 arch/arm/include/asm/page.h        |  5 +----
 arch/arm64/include/asm/page-def.h  |  5 +----
 arch/csky/include/asm/page.h       |  8 ++------
 arch/hexagon/include/asm/page.h    |  4 +---
 arch/loongarch/include/asm/page.h  |  7 +------
 arch/m68k/include/asm/page.h       |  6 ++----
 arch/microblaze/include/asm/page.h |  5 +----
 arch/mips/include/asm/page.h       |  7 +------
 arch/nios2/include/asm/page.h      |  7 +------
 arch/openrisc/include/asm/page.h   | 11 +----------
 arch/parisc/include/asm/page.h     |  4 +---
 arch/powerpc/include/asm/page.h    | 10 +---------
 arch/riscv/include/asm/page.h      |  4 +---
 arch/s390/include/asm/page.h       |  4 +---
 arch/sh/include/asm/page.h         |  6 ++----
 arch/sparc/include/asm/page_32.h   |  4 +---
 arch/sparc/include/asm/page_64.h   |  4 +---
 arch/um/include/asm/page.h         |  5 +----
 arch/x86/include/asm/page_types.h  |  5 +----
 arch/xtensa/include/asm/page.h     |  8 +-------
 drivers/gpu/drm/i915/gt/intel_gt.c |  2 +-
 include/vdso/page.h                | 23 +++++++++++++++++++++++
 24 files changed, 51 insertions(+), 106 deletions(-)
 create mode 100644 include/vdso/page.h

-- 
2.34.1

[PATCH v3 1/2] drm: Fix fault format

[Vincenzo Frascino]

Fault is of type u32 and PAGE_MASK is type agnostic, hence the correct
format for address should be %x not %lx otherwise:

drivers/gpu/drm/i915/gt/intel_gt_print.h:29:36: error: format ‘%lx’ expects
argument of type ‘long unsigned int’, but argument 6 has type ‘u32’ {aka
‘unsigned int’} [-Werror=format=]
   29 |         drm_dbg(&(_gt)->i915->drm, "GT%u: " _fmt, (_gt)->info.id,
      |                                    ^~~~~~~~
include/drm/drm_print.h:424:39: note: in definition of macro ‘drm_dev_dbg’
  424 |         __drm_dev_dbg(NULL, dev, cat, fmt, ##__VA_ARGS__)
      |                                       ^~~
include/drm/drm_print.h:524:33: note: in expansion of macro ‘drm_dbg_driver’
  524 | #define drm_dbg(drm, fmt, ...)  drm_dbg_driver(drm, fmt, ##__VA_ARGS__)
      |                                 ^~~~~~~~~~~~~~
linux/drivers/gpu/drm/i915/gt/intel_gt_print.h:29:9: note: in expansion of macro
‘drm_dbg’
   29 |         drm_dbg(&(_gt)->i915->drm, "GT%u: " _fmt, (_gt)->info.id,
      |         ^~~~~~~
drivers/gpu/drm/i915/gt/intel_gt.c:310:25: note: in expansion of macro ‘gt_dbg’
  310 |                         gt_dbg(gt, "Unexpected fault\n"
      |                         ^~~~~~

Fix address format.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
 drivers/gpu/drm/i915/gt/intel_gt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index a6c69a706fd7..352ef5e1c615 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -308,7 +308,7 @@ static void gen6_check_faults(struct intel_gt *gt)
 		fault = GEN6_RING_FAULT_REG_READ(engine);
 		if (fault & RING_FAULT_VALID) {
 			gt_dbg(gt, "Unexpected fault\n"
-			       "\tAddr: 0x%08lx\n"
+			       "\tAddr: 0x%08x\n"
 			       "\tAddress space: %s\n"
 			       "\tSource ID: %d\n"
 			       "\tType: %d\n",
-- 
2.34.1

[PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

The VDSO implementation includes headers from outside of the
vdso/ namespace.

Introduce vdso/page.h to make sure that the generic library
uses only the allowed namespace.

Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
it supports 64-bit phys_addr_t we might end up in situation in which the
top 32 bit are cleared. To prevent this issue this patch provides
separate macros for PAGE_MASK.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
 arch/alpha/include/asm/page.h      |  6 +-----
 arch/arc/include/uapi/asm/page.h   |  7 +++----
 arch/arm/include/asm/page.h        |  5 +----
 arch/arm64/include/asm/page-def.h  |  5 +----
 arch/csky/include/asm/page.h       |  8 ++------
 arch/hexagon/include/asm/page.h    |  4 +---
 arch/loongarch/include/asm/page.h  |  7 +------
 arch/m68k/include/asm/page.h       |  6 ++----
 arch/microblaze/include/asm/page.h |  5 +----
 arch/mips/include/asm/page.h       |  7 +------
 arch/nios2/include/asm/page.h      |  7 +------
 arch/openrisc/include/asm/page.h   | 11 +----------
 arch/parisc/include/asm/page.h     |  4 +---
 arch/powerpc/include/asm/page.h    | 10 +---------
 arch/riscv/include/asm/page.h      |  4 +---
 arch/s390/include/asm/page.h       |  4 +---
 arch/sh/include/asm/page.h         |  6 ++----
 arch/sparc/include/asm/page_32.h   |  4 +---
 arch/sparc/include/asm/page_64.h   |  4 +---
 arch/um/include/asm/page.h         |  5 +----
 arch/x86/include/asm/page_types.h  |  5 +----
 arch/xtensa/include/asm/page.h     |  8 +-------
 include/vdso/page.h                | 23 +++++++++++++++++++++++
 23 files changed, 50 insertions(+), 105 deletions(-)
 create mode 100644 include/vdso/page.h

diff --git a/arch/alpha/include/asm/page.h b/arch/alpha/include/asm/page.h
index 70419e6be1a3..261af54fd601 100644
--- a/arch/alpha/include/asm/page.h
+++ b/arch/alpha/include/asm/page.h
@@ -4,11 +4,7 @@
 
 #include <linux/const.h>
 #include <asm/pal.h>
-
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/arc/include/uapi/asm/page.h b/arch/arc/include/uapi/asm/page.h
index 7fd9e741b527..4606a326af5c 100644
--- a/arch/arc/include/uapi/asm/page.h
+++ b/arch/arc/include/uapi/asm/page.h
@@ -14,7 +14,7 @@
 
 /* PAGE_SHIFT determines the page size */
 #ifdef __KERNEL__
-#define PAGE_SHIFT CONFIG_PAGE_SHIFT
+#include <vdso/page.h>
 #else
 /*
  * Default 8k
@@ -24,11 +24,10 @@
  * not available
  */
 #define PAGE_SHIFT 13
+#define PAGE_SIZE	_BITUL(PAGE_SHIFT)	/* Default 8K */
+#define PAGE_MASK	(~(PAGE_SIZE-1))
 #endif
 
-#define PAGE_SIZE	_BITUL(PAGE_SHIFT)	/* Default 8K */
 #define PAGE_OFFSET	_AC(0x80000000, UL)	/* Kernel starts at 2G onwrds */
 
-#define PAGE_MASK	(~(PAGE_SIZE-1))
-
 #endif /* _UAPI__ASM_ARC_PAGE_H */
diff --git a/arch/arm/include/asm/page.h b/arch/arm/include/asm/page.h
index 62af9f7f9e96..ef11b721230e 100644
--- a/arch/arm/include/asm/page.h
+++ b/arch/arm/include/asm/page.h
@@ -7,10 +7,7 @@
 #ifndef _ASMARM_PAGE_H
 #define _ASMARM_PAGE_H
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT		CONFIG_PAGE_SHIFT
-#define PAGE_SIZE		(_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK		(~((1 << PAGE_SHIFT) - 1))
+#include <vdso/page.h>
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/arm64/include/asm/page-def.h b/arch/arm64/include/asm/page-def.h
index 792e9fe881dc..d402e08442ee 100644
--- a/arch/arm64/include/asm/page-def.h
+++ b/arch/arm64/include/asm/page-def.h
@@ -10,9 +10,6 @@
 
 #include <linux/const.h>
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT		CONFIG_PAGE_SHIFT
-#define PAGE_SIZE		(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK		(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #endif /* __ASM_PAGE_DEF_H */
diff --git a/arch/csky/include/asm/page.h b/arch/csky/include/asm/page.h
index 0ca6c408c07f..f8beae295afb 100644
--- a/arch/csky/include/asm/page.h
+++ b/arch/csky/include/asm/page.h
@@ -7,12 +7,8 @@
 #include <asm/cache.h>
 #include <linux/const.h>
 
-/*
- * PAGE_SHIFT determines the page size: 4KB
- */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE - 1))
+#include <vdso/page.h>
+
 #define THREAD_SIZE	(PAGE_SIZE * 2)
 #define THREAD_MASK	(~(THREAD_SIZE - 1))
 #define THREAD_SHIFT	(PAGE_SHIFT + 1)
diff --git a/arch/hexagon/include/asm/page.h b/arch/hexagon/include/asm/page.h
index 8a6af57274c2..b01f8df69dd4 100644
--- a/arch/hexagon/include/asm/page.h
+++ b/arch/hexagon/include/asm/page.h
@@ -45,9 +45,7 @@
 #define HVM_HUGEPAGE_SIZE 0x5
 #endif
 
-#define PAGE_SHIFT CONFIG_PAGE_SHIFT
-#define PAGE_SIZE  (1UL << PAGE_SHIFT)
-#define PAGE_MASK  (~((1 << PAGE_SHIFT) - 1))
+#include <vdso/page.h>
 
 #ifdef __KERNEL__
 #ifndef __ASSEMBLY__
diff --git a/arch/loongarch/include/asm/page.h b/arch/loongarch/include/asm/page.h
index e85df33f11c7..83f3533e31a4 100644
--- a/arch/loongarch/include/asm/page.h
+++ b/arch/loongarch/include/asm/page.h
@@ -8,12 +8,7 @@
 #include <linux/const.h>
 #include <asm/addrspace.h>
 
-/*
- * PAGE_SHIFT determines the page size
- */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE - 1))
+#include <vdso/page.h>
 
 #define HPAGE_SHIFT	(PAGE_SHIFT + PAGE_SHIFT - 3)
 #define HPAGE_SIZE	(_AC(1, UL) << HPAGE_SHIFT)
diff --git a/arch/m68k/include/asm/page.h b/arch/m68k/include/asm/page.h
index 8cfb84b49975..b173ba27d36f 100644
--- a/arch/m68k/include/asm/page.h
+++ b/arch/m68k/include/asm/page.h
@@ -6,10 +6,8 @@
 #include <asm/setup.h>
 #include <asm/page_offset.h>
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
+
 #define PAGE_OFFSET	(PAGE_OFFSET_RAW)
 
 #ifndef __ASSEMBLY__
diff --git a/arch/microblaze/include/asm/page.h b/arch/microblaze/include/asm/page.h
index 8810f4f1c3b0..d1ec3806edab 100644
--- a/arch/microblaze/include/asm/page.h
+++ b/arch/microblaze/include/asm/page.h
@@ -19,10 +19,7 @@
 
 #ifdef __KERNEL__
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(ASM_CONST(1) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #define LOAD_OFFSET	ASM_CONST((CONFIG_KERNEL_START-CONFIG_KERNEL_BASE_ADDR))
 
diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
index 4609cb0326cf..bc3e3484c1bf 100644
--- a/arch/mips/include/asm/page.h
+++ b/arch/mips/include/asm/page.h
@@ -14,12 +14,7 @@
 #include <linux/kernel.h>
 #include <asm/mipsregs.h>
 
-/*
- * PAGE_SHIFT determines the page size
- */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~((1 << PAGE_SHIFT) - 1))
+#include <vdso/page.h>
 
 /*
  * This is used for calculating the real page sizes
diff --git a/arch/nios2/include/asm/page.h b/arch/nios2/include/asm/page.h
index 0722f88e63cc..2897ec1b74f6 100644
--- a/arch/nios2/include/asm/page.h
+++ b/arch/nios2/include/asm/page.h
@@ -18,12 +18,7 @@
 #include <linux/pfn.h>
 #include <linux/const.h>
 
-/*
- * PAGE_SHIFT determines the page size
- */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE - 1))
+#include <vdso/page.h>
 
 /*
  * PAGE_OFFSET -- the first address of the first page of memory.
diff --git a/arch/openrisc/include/asm/page.h b/arch/openrisc/include/asm/page.h
index 1d5913f67c31..124a2db4b160 100644
--- a/arch/openrisc/include/asm/page.h
+++ b/arch/openrisc/include/asm/page.h
@@ -15,16 +15,7 @@
 #ifndef __ASM_OPENRISC_PAGE_H
 #define __ASM_OPENRISC_PAGE_H
 
-
-/* PAGE_SHIFT determines the page size */
-
-#define PAGE_SHIFT      CONFIG_PAGE_SHIFT
-#ifdef __ASSEMBLY__
-#define PAGE_SIZE       (1 << PAGE_SHIFT)
-#else
-#define PAGE_SIZE       (1UL << PAGE_SHIFT)
-#endif
-#define PAGE_MASK       (~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #define PAGE_OFFSET	0xc0000000
 #define KERNELBASE	PAGE_OFFSET
diff --git a/arch/parisc/include/asm/page.h b/arch/parisc/include/asm/page.h
index 4bea2e95798f..6c4836fb5407 100644
--- a/arch/parisc/include/asm/page.h
+++ b/arch/parisc/include/asm/page.h
@@ -4,9 +4,7 @@
 
 #include <linux/const.h>
 
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
 
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 83d0a4fc5f75..af9a2628d1df 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -21,8 +21,7 @@
  * page size. When using 64K pages however, whether we are really supporting
  * 64K pages in HW or not is irrelevant to those definitions.
  */
-#define PAGE_SHIFT		CONFIG_PAGE_SHIFT
-#define PAGE_SIZE		(ASM_CONST(1) << PAGE_SHIFT)
+#include <vdso/page.h>
 
 #ifndef __ASSEMBLY__
 #ifndef CONFIG_HUGETLB_PAGE
@@ -41,13 +40,6 @@ extern unsigned int hpage_shift;
 #define HUGE_MAX_HSTATE		(MMU_PAGE_COUNT-1)
 #endif
 
-/*
- * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we
- * assign PAGE_MASK to a larger type it gets extended the way we want
- * (i.e. with 1s in the high bits)
- */
-#define PAGE_MASK      (~((1 << PAGE_SHIFT) - 1))
-
 /*
  * KERNELBASE is the virtual address of the start of the kernel, it's often
  * the same as PAGE_OFFSET, but _might not be_.
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
index 32d308a3355f..9875399827c7 100644
--- a/arch/riscv/include/asm/page.h
+++ b/arch/riscv/include/asm/page.h
@@ -12,9 +12,7 @@
 #include <linux/pfn.h>
 #include <linux/const.h>
 
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE - 1))
+#include <vdso/page.h>
 
 #define HPAGE_SHIFT		PMD_SHIFT
 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
diff --git a/arch/s390/include/asm/page.h b/arch/s390/include/asm/page.h
index 73e1e03317b4..c949fe7736b9 100644
--- a/arch/s390/include/asm/page.h
+++ b/arch/s390/include/asm/page.h
@@ -11,9 +11,7 @@
 #include <linux/const.h>
 #include <asm/types.h>
 
-#define _PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define _PAGE_SIZE	(_AC(1, UL) << _PAGE_SHIFT)
-#define _PAGE_MASK	(~(_PAGE_SIZE - 1))
+#include <vdso/page.h>
 
 /* PAGE_SHIFT determines the page size */
 #define PAGE_SHIFT	_PAGE_SHIFT
diff --git a/arch/sh/include/asm/page.h b/arch/sh/include/asm/page.h
index f780b467e75d..fc39b8171bfb 100644
--- a/arch/sh/include/asm/page.h
+++ b/arch/sh/include/asm/page.h
@@ -8,10 +8,8 @@
 
 #include <linux/const.h>
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
+
 #define PTE_MASK	PAGE_MASK
 
 #if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
diff --git a/arch/sparc/include/asm/page_32.h b/arch/sparc/include/asm/page_32.h
index 9977c77374cd..9954254ea569 100644
--- a/arch/sparc/include/asm/page_32.h
+++ b/arch/sparc/include/asm/page_32.h
@@ -11,9 +11,7 @@
 
 #include <linux/const.h>
 
-#define PAGE_SHIFT   CONFIG_PAGE_SHIFT
-#define PAGE_SIZE    (_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK    (~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/sparc/include/asm/page_64.h b/arch/sparc/include/asm/page_64.h
index e9bd24821c93..2a68ff5b6eab 100644
--- a/arch/sparc/include/asm/page_64.h
+++ b/arch/sparc/include/asm/page_64.h
@@ -4,9 +4,7 @@
 
 #include <linux/const.h>
 
-#define PAGE_SHIFT   CONFIG_PAGE_SHIFT
-#define PAGE_SIZE    (_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK    (~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 /* Flushing for D-cache alias handling is only needed if
  * the page size is smaller than 16K.
diff --git a/arch/um/include/asm/page.h b/arch/um/include/asm/page.h
index 9ef9a8aedfa6..834313ecd3d6 100644
--- a/arch/um/include/asm/page.h
+++ b/arch/um/include/asm/page.h
@@ -9,10 +9,7 @@
 
 #include <linux/const.h>
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #ifndef __ASSEMBLY__
 
diff --git a/arch/x86/include/asm/page_types.h b/arch/x86/include/asm/page_types.h
index 52f1b4ff0cc1..974688973cf6 100644
--- a/arch/x86/include/asm/page_types.h
+++ b/arch/x86/include/asm/page_types.h
@@ -6,10 +6,7 @@
 #include <linux/types.h>
 #include <linux/mem_encrypt.h>
 
-/* PAGE_SHIFT determines the page size */
-#define PAGE_SHIFT		CONFIG_PAGE_SHIFT
-#define PAGE_SIZE		(_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK		(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #define __VIRTUAL_MASK		((1UL << __VIRTUAL_MASK_SHIFT) - 1)
 
diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h
index 4db56ef052d2..595c1037b738 100644
--- a/arch/xtensa/include/asm/page.h
+++ b/arch/xtensa/include/asm/page.h
@@ -18,13 +18,7 @@
 #include <asm/cache.h>
 #include <asm/kmem_layout.h>
 
-/*
- * PAGE_SHIFT determines the page size
- */
-
-#define PAGE_SHIFT	CONFIG_PAGE_SHIFT
-#define PAGE_SIZE	(__XTENSA_UL_CONST(1) << PAGE_SHIFT)
-#define PAGE_MASK	(~(PAGE_SIZE-1))
+#include <vdso/page.h>
 
 #ifdef CONFIG_MMU
 #define PAGE_OFFSET	XCHAL_KSEG_CACHED_VADDR
diff --git a/include/vdso/page.h b/include/vdso/page.h
new file mode 100644
index 000000000000..36693093665b
--- /dev/null
+++ b/include/vdso/page.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_PAGE_H
+#define __VDSO_PAGE_H
+
+#include <uapi/linux/const.h>
+
+/*
+ * PAGE_SHIFT determines the page size.
+ *
+ * Note: This definition is required because PAGE_SHIFT is used
+ * in several places throuout the codebase.
+ */
+#define PAGE_SHIFT      CONFIG_PAGE_SHIFT
+
+#define PAGE_SIZE	(_AC(1,UL) << CONFIG_PAGE_SHIFT)
+
+#if defined(CONFIG_PHYS_ADDR_T_64BIT)
+#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
+#else
+#define PAGE_MASK	(~(PAGE_SIZE-1))
+#endif
+
+#endif	/* __VDSO_PAGE_H */
-- 
2.34.1

Re: [PATCH v3 0/2] vdso: Use only headers from the vdso/ namespace

[Jason A. Donenfeld]

On Thu, Oct 03, 2024 at 04:29:08PM +0100, Vincenzo Frascino wrote:
> The series has been rebased on [1] to simplify the testing. 
> 
> [1] git://git.kernel.org/pub/scm/linux/kernel/git/crng/random.git master

Just FYI, tglx is doing some heavy vDSO work this cycle, so if this is
to land, it'll most likely go via his tip tree, not my random tree.

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Geert Uytterhoeven]

On Thu, Oct 3, 2024 at 5:30 PM Vincenzo Frascino
<vincenzo.frascino@arm.com> wrote:
> The VDSO implementation includes headers from outside of the
> vdso/ namespace.
>
> Introduce vdso/page.h to make sure that the generic library
> uses only the allowed namespace.
>
> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
> it supports 64-bit phys_addr_t we might end up in situation in which the
> top 32 bit are cleared. To prevent this issue this patch provides
> separate macros for PAGE_MASK.
>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jason A. Donenfeld <Jason@zx2c4.com>
> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>

Thanks for your patch!

>  arch/m68k/include/asm/page.h       |  6 ++----

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k

> --- /dev/null
> +++ b/include/vdso/page.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __VDSO_PAGE_H
> +#define __VDSO_PAGE_H
> +
> +#include <uapi/linux/const.h>
> +
> +/*
> + * PAGE_SHIFT determines the page size.
> + *
> + * Note: This definition is required because PAGE_SHIFT is used
> + * in several places throuout the codebase.

throughout

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Arnd Bergmann]

On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
> The VDSO implementation includes headers from outside of the
> vdso/ namespace.
>
> Introduce vdso/page.h to make sure that the generic library
> uses only the allowed namespace.
>
> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
> it supports 64-bit phys_addr_t we might end up in situation in which the
> top 32 bit are cleared. To prevent this issue this patch provides
> separate macros for PAGE_MASK.
>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jason A. Donenfeld <Jason@zx2c4.com>
> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>

Looks good to me. I would apply this to the asm-generic
tree for 6.13, but there is one small detail I'm unsure
about:

> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
> +#else
> +#define PAGE_MASK	(~(PAGE_SIZE-1))
> +#endif

We only want the #if branch for 32-bit architectures, right?

On 64-bit ones, CONFIG_PHYS_ADDR_T_64BIT is always set, so
I think that is unnecessary change from the existing version,
even though it should be harmless.

     Arnd

Re: [PATCH v3 1/2] drm: Fix fault format

[Arnd Bergmann]

On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c 
> b/drivers/gpu/drm/i915/gt/intel_gt.c
> index a6c69a706fd7..352ef5e1c615 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt.c
> @@ -308,7 +308,7 @@ static void gen6_check_faults(struct intel_gt *gt)
>  		fault = GEN6_RING_FAULT_REG_READ(engine);
>  		if (fault & RING_FAULT_VALID) {
>  			gt_dbg(gt, "Unexpected fault\n"
> -			       "\tAddr: 0x%08lx\n"
> +			       "\tAddr: 0x%08x\n"
>  			       "\tAddress space: %s\n"
>  			       "\tSource ID: %d\n"
>  			       "\tType: %d\n",

Isn't the type of PAGE_MASK still architecture dependent?
I think you need a cast to either 'int' or 'long' here to
make the corresponding format string work across all
architectures. With the current version of your patch 2/2,
it looks like it has to be %x for architectures with 
64-bit phys_addr_t, but %lx for the other ones.

Changing the 'u32 fault' variable to 'unsigned long'
would also work here.

      Arnd

Re: [PATCH v3 1/2] drm: Fix fault format

[Christophe Leroy]

Le 04/10/2024 à 15:21, Arnd Bergmann a écrit :
> On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
>> diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c
>> b/drivers/gpu/drm/i915/gt/intel_gt.c
>> index a6c69a706fd7..352ef5e1c615 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_gt.c
>> +++ b/drivers/gpu/drm/i915/gt/intel_gt.c
>> @@ -308,7 +308,7 @@ static void gen6_check_faults(struct intel_gt *gt)
>>   		fault = GEN6_RING_FAULT_REG_READ(engine);
>>   		if (fault & RING_FAULT_VALID) {
>>   			gt_dbg(gt, "Unexpected fault\n"
>> -			       "\tAddr: 0x%08lx\n"
>> +			       "\tAddr: 0x%08x\n"
>>   			       "\tAddress space: %s\n"
>>   			       "\tSource ID: %d\n"
>>   			       "\tType: %d\n",
> 
> Isn't the type of PAGE_MASK still architecture dependent?

Indeed when I commented that PAGE_MASK was type agnostic I was thinking 
about the powerpc PAGE_MASK:

#define PAGE_MASK      (~((1 << PAGE_SHIFT) - 1))

It should probably be possible to generalise it to all architectures.

But if you keep some PAGE_MASK with forced UL type just like:

#define PAGE_SIZE		(_AC(1, UL) << PAGE_SHIFT)
#define PAGE_MASK		(~(PAGE_SIZE-1))

Then that version of PAGE_MASK isn't agnostic and ANDing an int with 
that mask makes a long result.

> I think you need a cast to either 'int' or 'long' here to
> make the corresponding format string work across all
> architectures. With the current version of your patch 2/2,
> it looks like it has to be %x for architectures with
> 64-bit phys_addr_t, but %lx for the other ones.
> 
> Changing the 'u32 fault' variable to 'unsigned long'
> would also work here.
> 
>        Arnd

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

On 04/10/2024 14:13, Arnd Bergmann wrote:
> On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
>> The VDSO implementation includes headers from outside of the
>> vdso/ namespace.
>>
>> Introduce vdso/page.h to make sure that the generic library
>> uses only the allowed namespace.
>>
>> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
>> it supports 64-bit phys_addr_t we might end up in situation in which the
>> top 32 bit are cleared. To prevent this issue this patch provides
>> separate macros for PAGE_MASK.
>>
>> Cc: Arnd Bergmann <arnd@arndb.de>
>> Cc: Andy Lutomirski <luto@kernel.org>
>> Cc: Thomas Gleixner <tglx@linutronix.de>
>> Cc: Jason A. Donenfeld <Jason@zx2c4.com>
>> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
> 
> Looks good to me. I would apply this to the asm-generic
> tree for 6.13, but there is one small detail I'm unsure
> about:
>

Thanks.

>> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
>> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
>> +#else
>> +#define PAGE_MASK	(~(PAGE_SIZE-1))
>> +#endif
> 
> We only want the #if branch for 32-bit architectures, right?
> 
> On 64-bit ones, CONFIG_PHYS_ADDR_T_64BIT is always set, so
> I think that is unnecessary change from the existing version,
> even though it should be harmless.
> 

It seemed harmless from the tests I did. But adding an '&&
defined(CONFIG_32BIT)' makes it logically correct. I will add a comment as well
in the next version.

>      Arnd

-- 
Regards,
Vincenzo

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Arnd Bergmann]

On Mon, Oct 7, 2024, at 11:01, Vincenzo Frascino wrote:
> On 04/10/2024 14:13, Arnd Bergmann wrote:

>
> It seemed harmless from the tests I did. But adding an '&&
> defined(CONFIG_32BIT)' makes it logically correct. I will add a comment as well
> in the next version.

To clarify: this has to be "!defined(CONFIG_64BIT)", as most
32-bit architectures don't define the CONFIG_32BIT symbol
(but all 64-bit ones define CONFIG_64BIT).

    Arnd

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

On 07/10/2024 12:06, Arnd Bergmann wrote:
> On Mon, Oct 7, 2024, at 11:01, Vincenzo Frascino wrote:
>> On 04/10/2024 14:13, Arnd Bergmann wrote:
> 
>>
>> It seemed harmless from the tests I did. But adding an '&&
>> defined(CONFIG_32BIT)' makes it logically correct. I will add a comment as well
>> in the next version.
> 
> To clarify: this has to be "!defined(CONFIG_64BIT)", as most
> 32-bit architectures don't define the CONFIG_32BIT symbol
> (but all 64-bit ones define CONFIG_64BIT).
> 

You are right, it seemed that every 32-bit architectures with a
64-bit phys_addr_t had CONFIG_32BIT but this is not the case.

>     Arnd

-- 
Regards,
Vincenzo

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[H. Peter Anvin]

On October 7, 2024 4:20:23 AM PDT, Vincenzo Frascino <vincenzo.frascino@arm.com> wrote:
>
>
>On 07/10/2024 12:06, Arnd Bergmann wrote:
>> On Mon, Oct 7, 2024, at 11:01, Vincenzo Frascino wrote:
>>> On 04/10/2024 14:13, Arnd Bergmann wrote:
>> 
>>>
>>> It seemed harmless from the tests I did. But adding an '&&
>>> defined(CONFIG_32BIT)' makes it logically correct. I will add a comment as well
>>> in the next version.
>> 
>> To clarify: this has to be "!defined(CONFIG_64BIT)", as most
>> 32-bit architectures don't define the CONFIG_32BIT symbol
>> (but all 64-bit ones define CONFIG_64BIT).
>> 
>
>You are right, it seemed that every 32-bit architectures with a
>64-bit phys_addr_t had CONFIG_32BIT but this is not the case.
>
>>     Arnd
>

Maybe we should have CONFIG_32BIT as a global?

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Thomas Gleixner]

On Fri, Oct 04 2024 at 13:13, Arnd Bergmann wrote:
> On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
>> The VDSO implementation includes headers from outside of the
>> vdso/ namespace.
>>
>> Introduce vdso/page.h to make sure that the generic library
>> uses only the allowed namespace.
>>
>> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
>> it supports 64-bit phys_addr_t we might end up in situation in which the
>> top 32 bit are cleared. To prevent this issue this patch provides
>> separate macros for PAGE_MASK.
>>
>> Cc: Arnd Bergmann <arnd@arndb.de>
>> Cc: Andy Lutomirski <luto@kernel.org>
>> Cc: Thomas Gleixner <tglx@linutronix.de>
>> Cc: Jason A. Donenfeld <Jason@zx2c4.com>
>> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
>
> Looks good to me. I would apply this to the asm-generic
> tree for 6.13, but there is one small detail I'm unsure
> about:

Please don't. We have related changes upcoming for VDSO which would
heavily conflict. I rather take it through my tree.

Thanks,

        tglx

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Arnd Bergmann]

On Mon, Oct 7, 2024, at 16:23, Thomas Gleixner wrote:
> On Fri, Oct 04 2024 at 13:13, Arnd Bergmann wrote:
>> On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
>>> The VDSO implementation includes headers from outside of the
>>> vdso/ namespace.
>>>
>>> Introduce vdso/page.h to make sure that the generic library
>>> uses only the allowed namespace.
>>>
>>> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
>>> it supports 64-bit phys_addr_t we might end up in situation in which the
>>> top 32 bit are cleared. To prevent this issue this patch provides
>>> separate macros for PAGE_MASK.
>>>
>>> Cc: Arnd Bergmann <arnd@arndb.de>
>>> Cc: Andy Lutomirski <luto@kernel.org>
>>> Cc: Thomas Gleixner <tglx@linutronix.de>
>>> Cc: Jason A. Donenfeld <Jason@zx2c4.com>
>>> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
>>
>> Looks good to me. I would apply this to the asm-generic
>> tree for 6.13, but there is one small detail I'm unsure
>> about:
>
> Please don't. We have related changes upcoming for VDSO which would
> heavily conflict. I rather take it through my tree.

Ok.

Vincenzo, in that case please add 

Reviewed-by: Arnd Bergmann <arnd@arndb.de>

to the two paches when you send v4 to Thomas.

     Arnd

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

On 08/10/2024 14:11, Arnd Bergmann wrote:
> On Mon, Oct 7, 2024, at 16:23, Thomas Gleixner wrote:
>> On Fri, Oct 04 2024 at 13:13, Arnd Bergmann wrote:
>>> On Thu, Oct 3, 2024, at 15:29, Vincenzo Frascino wrote:
>>>> The VDSO implementation includes headers from outside of the
>>>> vdso/ namespace.
>>>>
>>>> Introduce vdso/page.h to make sure that the generic library
>>>> uses only the allowed namespace.
>>>>
>>>> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
>>>> it supports 64-bit phys_addr_t we might end up in situation in which the
>>>> top 32 bit are cleared. To prevent this issue this patch provides
>>>> separate macros for PAGE_MASK.
>>>>
>>>> Cc: Arnd Bergmann <arnd@arndb.de>
>>>> Cc: Andy Lutomirski <luto@kernel.org>
>>>> Cc: Thomas Gleixner <tglx@linutronix.de>
>>>> Cc: Jason A. Donenfeld <Jason@zx2c4.com>
>>>> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
>>>
>>> Looks good to me. I would apply this to the asm-generic
>>> tree for 6.13, but there is one small detail I'm unsure
>>> about:
>>
>> Please don't. We have related changes upcoming for VDSO which would
>> heavily conflict. I rather take it through my tree.
> 
> Ok.
> 
> Vincenzo, in that case please add 
> 
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> 
> to the two paches when you send v4 to Thomas.
>

Thank you Arnd and Thomas,

I am completing the testing and will do that.

>      Arnd

-- 
Regards,
Vincenzo

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Thomas Gleixner]

On Thu, Oct 03 2024 at 16:29, Vincenzo Frascino wrote:
> The VDSO implementation includes headers from outside of the
> vdso/ namespace.
>
> Introduce vdso/page.h to make sure that the generic library
> uses only the allowed namespace.
>
> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
> it supports 64-bit phys_addr_t we might end up in situation in which
> the

We end up with nothing.

> top 32 bit are cleared. To prevent this issue this patch provides
> separate macros for PAGE_MASK.

'this patch' is redundant information.

git grep 'This patch' Documentation/process/

> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __VDSO_PAGE_H
> +#define __VDSO_PAGE_H
> +
> +#include <uapi/linux/const.h>
> +
> +/*
> + * PAGE_SHIFT determines the page size.
> + *
> + * Note: This definition is required because PAGE_SHIFT is used
> + * in several places throuout the codebase.
> + */
> +#define PAGE_SHIFT      CONFIG_PAGE_SHIFT
> +
> +#define PAGE_SIZE	(_AC(1,UL) << CONFIG_PAGE_SHIFT)
> +
> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
> +#else
> +#define PAGE_MASK	(~(PAGE_SIZE-1))

#define PAGE_MASK	(~(PAGE_SIZE - 1))

please.

Thanks,

        tglx

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Thomas Gleixner]

On Wed, Oct 09 2024 at 11:53, Thomas Gleixner wrote:
> On Thu, Oct 03 2024 at 16:29, Vincenzo Frascino wrote:

Hit send too early.

>> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
>> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))

This really wants a comment. The magic reliance on integer sign
expansion is any thing than obvious.

Thanks,

         tglx

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Michael Ellerman]

Thomas Gleixner <tglx@linutronix.de> writes:
> On Wed, Oct 09 2024 at 11:53, Thomas Gleixner wrote:
>> On Thu, Oct 03 2024 at 16:29, Vincenzo Frascino wrote:
>
> Hit send too early.
>
>>> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
>>> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
>
> This really wants a comment. The magic reliance on integer sign
> expansion is any thing than obvious.

+1

Vincenzo feel free to take/modify the one from arch/powerpc/include/asm/page.h :)

cheers

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

On 09/10/2024 10:53, Thomas Gleixner wrote:
> On Thu, Oct 03 2024 at 16:29, Vincenzo Frascino wrote:
>> The VDSO implementation includes headers from outside of the
>> vdso/ namespace.
>>
>> Introduce vdso/page.h to make sure that the generic library
>> uses only the allowed namespace.
>>
>> Note: on a 32-bit architecture UL is an unsigned 32 bit long. Hence when
>> it supports 64-bit phys_addr_t we might end up in situation in which
>> the
> 
> We end up with nothing.
> 
>> top 32 bit are cleared. To prevent this issue this patch provides
>> separate macros for PAGE_MASK.
> 
> 'this patch' is redundant information.
> 
> git grep 'This patch' Documentation/process/
> 

My bad, I thought that Documentation/process/submitting-patches.rst referred
only to the proposed change which is in imperative mood.

I will rephrase it accordingly.

...

>> +#define PAGE_MASK	(~(PAGE_SIZE-1))
> 
> #define PAGE_MASK	(~(PAGE_SIZE - 1))
> 
> please.
>

Will change it in v4.

> Thanks,
> 
>         tglx

-- 
Regards,
Vincenzo

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

On 09/10/2024 11:04, Thomas Gleixner wrote:
> On Wed, Oct 09 2024 at 11:53, Thomas Gleixner wrote:
>> On Thu, Oct 03 2024 at 16:29, Vincenzo Frascino wrote:
> 
> Hit send too early.
> 
>>> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
>>> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
> 
> This really wants a comment. The magic reliance on integer sign
> expansion is any thing than obvious.
> 

Sure, I will add one. Thanks.

> Thanks,
> 
>          tglx

-- 
Regards,
Vincenzo

Re: [PATCH v3 2/2] vdso: Introduce vdso/page.h

[Vincenzo Frascino]

On 10/10/2024 00:58, Michael Ellerman wrote:
> Thomas Gleixner <tglx@linutronix.de> writes:
>> On Wed, Oct 09 2024 at 11:53, Thomas Gleixner wrote:
>>> On Thu, Oct 03 2024 at 16:29, Vincenzo Frascino wrote:
>>
>> Hit send too early.
>>
>>>> +#if defined(CONFIG_PHYS_ADDR_T_64BIT)
>>>> +#define PAGE_MASK	(~((1 << CONFIG_PAGE_SHIFT) - 1))
>>
>> This really wants a comment. The magic reliance on integer sign
>> expansion is any thing than obvious.
> 
> +1
> 
> Vincenzo feel free to take/modify the one from arch/powerpc/include/asm/page.h :)
> 

I will, thank you :)

> cheers

-- 
Regards,
Vincenzo