0e799e840a
Some users want to pass NULL to drm_gem_object_put(), but those using
__drm_gem_object_put() did not. Compromise, have both and let the
compiler sort it out.
drm_gem_fb_destroy() calls drm_gem_object_put() with NULL obj causing:
[ 11.584209] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 11.584213] #PF: supervisor write access in kernel mode
[ 11.584215] #PF: error_code(0x0002) - not-present page
[ 11.584216] PGD 0 P4D 0
[ 11.584220] Oops: 0002 [#1] SMP NOPTI
[ 11.584223] CPU: 7 PID: 1571 Comm: gnome-shell Tainted: G E 5.7.0-rc1-1-default+ #27
[ 11.584225] Hardware name: Micro-Star International Co., Ltd. MS-7A31/X370 XPOWER GAMING TITANIUM (MS-7A31), BIOS 1.MR 12/03/2019
[ 11.584237] RIP: 0010:drm_gem_fb_destroy+0x28/0x70 [drm_kms_helper]
<snip>
[ 11.584256] Call Trace:
[ 11.584279] drm_mode_rmfb+0x189/0x1c0 [drm]
[ 11.584299] ? drm_mode_rmfb+0x1c0/0x1c0 [drm]
[ 11.584314] drm_ioctl_kernel+0xaa/0xf0 [drm]
[ 11.584329] drm_ioctl+0x1ff/0x3b0 [drm]
[ 11.584347] ? drm_mode_rmfb+0x1c0/0x1c0 [drm]
[ 11.584421] amdgpu_drm_ioctl+0x49/0x80 [amdgpu]
[ 11.584427] ksys_ioctl+0x87/0xc0
[ 11.584430] __x64_sys_ioctl+0x16/0x20
[ 11.584434] do_syscall_64+0x5f/0x240
[ 11.584438] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 11.584440] RIP: 0033:0x7f0ef80f7227
Reported-by: Nirmoy Das <nirmoy.das@amd.com>
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| 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.