mirror of
https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git
synced 2026-10-08 21:22:09 -04:00
No description
- C 98.2%
- Assembly 1%
- Makefile 0.3%
- Shell 0.2%
- Python 0.1%
| Filename | Latest commit message | Latest commit date |
|---|---|---|
cc66b6bb32
[ Upstream commit 269b3a9ac538c4ae87f84be640b9fa89914a2489 ]
In the current code, if CONFIG_SWIOTLB is set, when failed to get IO TLB
memory from the low pages by plat_swiotlb_setup(), it may lead to the boot
process failed with kernel panic.
(1) On the Loongson and SiByte platform
arch/mips/loongson64/dma.c
arch/mips/sibyte/common/dma.c
void __init plat_swiotlb_setup(void)
{
swiotlb_init(1);
}
kernel/dma/swiotlb.c
void __init
swiotlb_init(int verbose)
{
...
vstart = memblock_alloc_low(PAGE_ALIGN(bytes), PAGE_SIZE);
if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))
return;
...
pr_warn("Cannot allocate buffer");
no_iotlb_memory = true;
}
phys_addr_t swiotlb_tbl_map_single()
{
...
if (no_iotlb_memory)
panic("Can not allocate SWIOTLB buffer earlier ...");
...
}
(2) On the Cavium OCTEON platform
arch/mips/cavium-octeon/dma-octeon.c
void __init plat_swiotlb_setup(void)
{
...
octeon_swiotlb = memblock_alloc_low(swiotlbsize, PAGE_SIZE);
if (!octeon_swiotlb)
panic("%s: Failed to allocate %zu bytes align=%lx\n",
__func__, swiotlbsize, PAGE_SIZE);
...
}
Because IO_TLB_DEFAULT_SIZE is 64M, if the rest size of low memory is less
than 64M when call plat_swiotlb_setup(), we can easily reproduce the panic
case.
In order to reduce the possibility of kernel panic when failed to get IO
TLB memory under CONFIG_SWIOTLB, it is better to allocate low memory as
small as possible before plat_swiotlb_setup(), so make sparse_init() using
top-down allocation.
Reported-by: Juxin Gao <gaojuxin@loongson.cn>
Co-developed-by: Juxin Gao <gaojuxin@loongson.cn>
Signed-off-by: Juxin Gao <gaojuxin@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
|
||
| 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.