Hi Andrew, Please ignore my previous email. It was another bug context. This patch has been applied and tested LTP sched test cases on x86 and the reported bug fixed. > From: Liam Howlett <liam.howlett@xxxxxxxxxx> > Subject: maple_tree: fix 32b parent pointers > Date: Tue, 17 May 2022 15:22:20 +0000 > > 32 bit parent pointers need an extra bit to account for increased slot > count. Update the constants and documentation to use the remaining high > bit. > > Link: https://lkml.kernel.org/r/20220517152209.3486724-1-Liam.Howlett@xxxxxxxxxx > Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> > Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx> > Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx> > --- > > include/linux/maple_tree.h | 2 +- > lib/maple_tree.c | 14 +++++++------- > 2 files changed, 8 insertions(+), 8 deletions(-) > > --- a/include/linux/maple_tree.h~maple-tree-add-new-data-structure-fix-3 > +++ a/include/linux/maple_tree.h > @@ -37,7 +37,7 @@ > #define MAPLE_NODE_SLOTS 63 /* 256 bytes including ->parent */ > #define MAPLE_RANGE64_SLOTS 32 /* 256 bytes */ > #define MAPLE_ARANGE64_SLOTS 21 /* 240 bytes */ > -#define MAPLE_ARANGE64_META_MAX 22 /* Out of range for metadata */ > +#define MAPLE_ARANGE64_META_MAX 31 /* Out of range for metadata */ > #define MAPLE_ALLOC_SLOTS (MAPLE_NODE_SLOTS - 2) > #endif /* defined(CONFIG_64BIT) || defined(BUILD_VDSO32_64) */ > > --- a/lib/maple_tree.c~maple-tree-add-new-data-structure-fix-3 > +++ a/lib/maple_tree.c > @@ -354,7 +354,7 @@ static inline bool mt_is_alloc(struct ma > /* > * The Parent Pointer > * Excluding root, the parent pointer is 256B aligned like all other tree nodes. > - * When storing a 32 or 64 bit values, the offset can fit into 4 bits. The 16 > + * When storing a 32 or 64 bit values, the offset can fit into 5 bits. The 16 > * bit values need an extra bit to store the offset. This extra bit comes from > * a reuse of the last bit in the node type. This is possible by using bit 1 to > * indicate if bit 2 is part of the type or the slot. > @@ -366,19 +366,19 @@ static inline bool mt_is_alloc(struct ma > * 0x110 = 64 bit nodes > * > * Slot size and alignment > - * 0x??1 : Root > - * 0x?00 : 16 bit values, type in 0-1, slot in 2-6 > - * 0x010 : 32 bit values, type in 0-2, slot in 3-6 > - * 0x110 : 64 bit values, type in 0-2, slot in 3-6 > + * 0b??1 : Root > + * 0b?00 : 16 bit values, type in 0-1, slot in 2-7 > + * 0b010 : 32 bit values, type in 0-2, slot in 3-7 > + * 0b110 : 64 bit values, type in 0-2, slot in 3-7 > */ > > #define MAPLE_PARENT_ROOT 0x01 > > #define MAPLE_PARENT_SLOT_SHIFT 0x03 > -#define MAPLE_PARENT_SLOT_MASK 0x78 > +#define MAPLE_PARENT_SLOT_MASK 0xF8 > > #define MAPLE_PARENT_16B_SLOT_SHIFT 0x02 > -#define MAPLE_PARENT_16B_SLOT_MASK 0x7C > +#define MAPLE_PARENT_16B_SLOT_MASK 0xFC > > #define MAPLE_PARENT_RANGE64 0x06 > #define MAPLE_PARENT_RANGE32 0x04 > _ > > Patches currently in -mm which might be from liam.howlett@xxxxxxxxxx are > > maple-tree-add-new-data-structure-fix.patch > maple-tree-add-new-data-structure-fix-2.patch > maple-tree-add-new-data-structure-fix-3.patch > lib-test_maple_tree-add-testing-for-maple-tree-fix.patch > mm-start-tracking-vmas-with-maple-tree-fix-2.patch > mm-remove-the-vma-linked-list-fix.patch >
