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| author | Helge Deller <deller@gmx.de> | 2023-08-07 20:04:09 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-08-08 12:37:01 -0600 |
| commit | 56675f8b9f9b15b024b8e3145fa289b004916ab7 (patch) | |
| tree | 864ebcfd3ea0c76fe6df5cefc177b5f0ee45d85b | |
| parent | 72dbde0f2afbe4af8e8595a89c650ae6b9d9c36f (diff) | |
| download | linux-56675f8b9f9b15b024b8e3145fa289b004916ab7.tar.gz | |
io_uring/parisc: Adjust pgoff in io_uring mmap() for parisc
The changes from commit 32832a407a71 ("io_uring: Fix io_uring mmap() by
using architecture-provided get_unmapped_area()") to the parisc
implementation of get_unmapped_area() broke glibc's locale-gen
executable when running on parisc.
This patch reverts those architecture-specific changes, and instead
adjusts in io_uring_mmu_get_unmapped_area() the pgoff offset which is
then given to parisc's get_unmapped_area() function. This is much
cleaner than the previous approach, and we still will get a coherent
addresss.
This patch has no effect on other architectures (SHM_COLOUR is only
defined on parisc), and the liburing testcase stil passes on parisc.
Cc: stable@vger.kernel.org # 6.4
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Fixes: 32832a407a71 ("io_uring: Fix io_uring mmap() by using architecture-provided get_unmapped_area()")
Fixes: d808459b2e31 ("io_uring: Adjust mapping wrt architecture aliasing requirements")
Link: https://lore.kernel.org/r/ZNEyGV0jyI8kOOfz@p100
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | arch/parisc/kernel/sys_parisc.c | 15 | ||||
| -rw-r--r-- | io_uring/io_uring.c | 3 |
2 files changed, 8 insertions, 10 deletions
diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c index ca2d537e25b18..9915062d5243c 100644 --- a/arch/parisc/kernel/sys_parisc.c +++ b/arch/parisc/kernel/sys_parisc.c @@ -27,17 +27,12 @@ #include <linux/elf-randomize.h> /* - * Construct an artificial page offset for the mapping based on the virtual + * Construct an artificial page offset for the mapping based on the physical * address of the kernel file mapping variable. - * If filp is zero the calculated pgoff value aliases the memory of the given - * address. This is useful for io_uring where the mapping shall alias a kernel - * address and a userspace adress where both the kernel and the userspace - * access the same memory region. */ -#define GET_FILP_PGOFF(filp, addr) \ - ((filp ? (((unsigned long) filp->f_mapping) >> 8) \ - & ((SHM_COLOUR-1) >> PAGE_SHIFT) : 0UL) \ - + (addr >> PAGE_SHIFT)) +#define GET_FILP_PGOFF(filp) \ + (filp ? (((unsigned long) filp->f_mapping) >> 8) \ + & ((SHM_COLOUR-1) >> PAGE_SHIFT) : 0UL) static unsigned long shared_align_offset(unsigned long filp_pgoff, unsigned long pgoff) @@ -117,7 +112,7 @@ static unsigned long arch_get_unmapped_area_common(struct file *filp, do_color_align = 0; if (filp || (flags & MAP_SHARED)) do_color_align = 1; - filp_pgoff = GET_FILP_PGOFF(filp, addr); + filp_pgoff = GET_FILP_PGOFF(filp); if (flags & MAP_FIXED) { /* Even MAP_FIXED mappings must reside within TASK_SIZE */ diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index f4591b912ea8e..93db3e4e7b688 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3470,6 +3470,8 @@ static unsigned long io_uring_mmu_get_unmapped_area(struct file *filp, * - use the kernel virtual address of the shared io_uring context * (instead of the userspace-provided address, which has to be 0UL * anyway). + * - use the same pgoff which the get_unmapped_area() uses to + * calculate the page colouring. * For architectures without such aliasing requirements, the * architecture will return any suitable mapping because addr is 0. */ @@ -3478,6 +3480,7 @@ static unsigned long io_uring_mmu_get_unmapped_area(struct file *filp, pgoff = 0; /* has been translated to ptr above */ #ifdef SHM_COLOUR addr = (uintptr_t) ptr; + pgoff = addr >> PAGE_SHIFT; #else addr = 0UL; #endif |