9377de4cb3
The function xe_vm_prepare_vma was blindly accepting zero as the number of fences and forwarded that to drm_exec_prepare_obj. However, that leads to an out-of-bounds shift in the dma_resv_reserve_fences() and while one could argue that the dma_resv code should be robust against that, avoid attempting to reserve zero fences. Relevant stack trace: [773.183188] ------------[ cut here ]------------ [773.183199] UBSAN: shift-out-of-bounds in ../include/linux/log2.h:57:13 [773.183241] shift exponent 64 is too large for 64-bit type 'long unsigned int' [773.183254] CPU: 2 PID: 1816 Comm: xe_evict Tainted: G U 6.8.0-rc3-xe #1 [773.183256] Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 2014 10/14/2022 [773.183257] Call Trace: [773.183258] <TASK> [773.183260] dump_stack_lvl+0xaf/0xd0 [773.183266] dump_stack+0x10/0x20 [773.183283] ubsan_epilogue+0x9/0x40 [773.183286] __ubsan_handle_shift_out_of_bounds+0x10f/0x170 [773.183293] dma_resv_reserve_fences.cold+0x2b/0x48 [773.183295] ? ww_mutex_lock+0x3c/0x110 [773.183301] drm_exec_prepare_obj+0x45/0x60 [drm_exec] [773.183313] xe_vm_prepare_vma+0x33/0x70 [xe] [773.183375] xe_vma_destroy_unlocked+0x55/0xa0 [xe] [773.183427] xe_vm_close_and_put+0x526/0x940 [xe] Fixes: |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.