| b8a25bbb | 05-Apr-2018 |
Dimitris Papastamos <dimitris.papastamos@arm.com> |
Implement static workaround for CVE-2018-3639
For affected CPUs, this approach enables the mitigation during EL3
initialization, following every PE reset. No mechanism is provided to
disable the mit
Implement static workaround for CVE-2018-3639
For affected CPUs, this approach enables the mitigation during EL3
initialization, following every PE reset. No mechanism is provided to
disable the mitigation at runtime.
This approach permanently mitigates the entire software stack and no
additional mitigation code is required in other software components.
TF-A implements this approach for the following affected CPUs:
* Cortex-A57 and Cortex-A72, by setting bit 55 (Disable load pass store) of
`CPUACTLR_EL1` (`S3_1_C15_C2_0`).
* Cortex-A73, by setting bit 3 of `S3_0_C15_C0_0` (not documented in the
Technical Reference Manual (TRM)).
* Cortex-A75, by setting bit 35 (reserved in TRM) of `CPUACTLR_EL1`
(`S3_0_C15_C1_0`).
Additionally, a new SMC interface is implemented to allow software
executing in lower ELs to discover whether the system is mitigated
against CVE-2018-3639.
Refer to "Firmware interfaces for mitigating cache speculation
vulnerabilities System Software on Arm Systems"[0] for more
information.
[0] https://developer.arm.com/cache-speculation-vulnerability-firmware-specification
Change-Id: I084aa7c3bc7c26bf2df2248301270f77bed22ceb
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>
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| 0a2d5b43 | 02-Feb-2018 |
Masahiro Yamada <yamada.masahiro@socionext.com> |
types: use int-ll64 for both aarch32 and aarch64
Since commit 031dbb122472 ("AArch32: Add essential Arch helpers"),
it is difficult to use consistent format strings for printf() family
between aarch
types: use int-ll64 for both aarch32 and aarch64
Since commit 031dbb122472 ("AArch32: Add essential Arch helpers"),
it is difficult to use consistent format strings for printf() family
between aarch32 and aarch64.
For example, uint64_t is defined as 'unsigned long long' for aarch32
and as 'unsigned long' for aarch64. Likewise, uintptr_t is defined
as 'unsigned int' for aarch32, and as 'unsigned long' for aarch64.
A problem typically arises when you use printf() in common code.
One solution could be, to cast the arguments to a type long enough
for both architectures. For example, if 'val' is uint64_t type,
like this:
printf("val = %llx\n", (unsigned long long)val);
Or, somebody may suggest to use a macro provided by <inttypes.h>,
like this:
printf("val = %" PRIx64 "\n", val);
But, both would make the code ugly.
The solution adopted in Linux kernel is to use the same typedefs for
all architectures. The fixed integer types in the kernel-space have
been unified into int-ll64, like follows:
typedef signed char int8_t;
typedef unsigned char uint8_t;
typedef signed short int16_t;
typedef unsigned short uint16_t;
typedef signed int int32_t;
typedef unsigned int uint32_t;
typedef signed long long int64_t;
typedef unsigned long long uint64_t;
[ Linux commit: 0c79a8e29b5fcbcbfd611daf9d500cfad8370fcf ]
This gets along with the codebase shared between 32 bit and 64 bit,
with the data model called ILP32, LP64, respectively.
The width for primitive types is defined as follows:
ILP32 LP64
int 32 32
long 32 64
long long 64 64
pointer 32 64
'long long' is 64 bit for both, so it is used for defining uint64_t.
'long' has the same width as pointer, so for uintptr_t.
We still need an ifdef conditional for (s)size_t.
All 64 bit architectures use "unsigned long" size_t, and most 32 bit
architectures use "unsigned int" size_t. H8/300, S/390 are known as
exceptions; they use "unsigned long" size_t despite their architecture
is 32 bit.
One idea for simplification might be to define size_t as 'unsigned long'
across architectures, then forbid the use of "%z" string format.
However, this would cause a distortion between size_t and sizeof()
operator. We have unknowledge about the native type of sizeof(), so
we need a guess of it anyway. I want the following formula to always
return 1:
__builtin_types_compatible_p(size_t, typeof(sizeof(int)))
Fortunately, ARM is probably a majority case. As far as I know, all
32 bit ARM compilers use "unsigned int" size_t.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
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