6.15-stable review patch. If anyone has any objections, please let me know.
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From: Haren Myneni haren@linux.ibm.com
[ Upstream commit 0d67f0dee6c9176bc09a5482dd7346e3a0f14d0b ]
The user space calls mmap() to map VAS window paste address and the kernel returns the complete mapped page for each window. So return -EINVAL if non-zero is passed for offset parameter to mmap().
See Documentation/arch/powerpc/vas-api.rst for mmap() restrictions.
Co-developed-by: Jonathan Greental yonatan02greental@gmail.com Signed-off-by: Jonathan Greental yonatan02greental@gmail.com Reported-by: Jonathan Greental yonatan02greental@gmail.com Fixes: dda44eb29c23 ("powerpc/vas: Add VAS user space API") Signed-off-by: Haren Myneni haren@linux.ibm.com Signed-off-by: Madhavan Srinivasan maddy@linux.ibm.com Link: https://patch.msgid.link/20250610021227.361980-2-maddy@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/platforms/book3s/vas-api.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/arch/powerpc/platforms/book3s/vas-api.c b/arch/powerpc/platforms/book3s/vas-api.c index 0b6365d85d117..dc6f75d3ac6ef 100644 --- a/arch/powerpc/platforms/book3s/vas-api.c +++ b/arch/powerpc/platforms/book3s/vas-api.c @@ -521,6 +521,15 @@ static int coproc_mmap(struct file *fp, struct vm_area_struct *vma) return -EINVAL; }
+ /* + * Map complete page to the paste address. So the user + * space should pass 0ULL to the offset parameter. + */ + if (vma->vm_pgoff) { + pr_debug("Page offset unsupported to map paste address\n"); + return -EINVAL; + } + /* Ensure instance has an open send window */ if (!txwin) { pr_err("No send window open?\n");