| a5640252 | 27-Apr-2017 |
Antonio Nino Diaz <antonio.ninodiaz@arm.com> |
Fix execute-never permissions in xlat tables libs
Translation regimes that only support one virtual address space (such as
the ones for EL2 and EL3) can flag memory regions as execute-never by
setti
Fix execute-never permissions in xlat tables libs
Translation regimes that only support one virtual address space (such as
the ones for EL2 and EL3) can flag memory regions as execute-never by
setting to 1 the XN bit in the Upper Attributes field in the translation
tables descriptors. Translation regimes that support two different
virtual address spaces (such as the one shared by EL1 and EL0) use bits
PXN and UXN instead.
The Trusted Firmware runs at EL3 and EL1, it has to handle translation
tables of both translation regimes, but the previous code handled both
regimes the same way, as if both had only 1 VA range.
When trying to set a descriptor as execute-never it would set the XN
bit correctly in EL3, but it would set the XN bit in EL1 as well. XN is
at the same bit position as UXN, which means that EL0 was being
prevented from executing code at this region, not EL1 as the code
intended. Therefore, the PXN bit was unset to 0 all the time. The result
is that, in AArch64 mode, read-only data sections of BL2 weren't
protected from being executed.
This patch adds support of translation regimes with two virtual address
spaces to both versions of the translation tables library, fixing the
execute-never permissions for translation tables in EL1.
The library currently does not support initializing translation tables
for EL0 software, therefore it does not set/unset the UXN bit. If EL1
software needs to initialize translation tables for EL0 software, it
should use a different library instead.
Change-Id: If27588f9820ff42988851d90dc92801c8ecbe0c9
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
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| ccbec91c | 24-Feb-2017 |
Antonio Nino Diaz <antonio.ninodiaz@arm.com> |
Apply workaround for errata 813419 of Cortex-A57
TLBI instructions for EL3 won't have the desired effect under specific
circumstances in Cortex-A57 r0p0. The workaround is to execute DSB and
TLBI tw
Apply workaround for errata 813419 of Cortex-A57
TLBI instructions for EL3 won't have the desired effect under specific
circumstances in Cortex-A57 r0p0. The workaround is to execute DSB and
TLBI twice each time.
Even though this errata is only needed in r0p0, the current errata
framework is not prepared to apply run-time workarounds. The current one
is always applied if compiled in, regardless of the CPU or its revision.
This errata has been enabled for Juno.
The `DSB` instruction used when initializing the translation tables has
been changed to `DSB ISH` as an optimization and to be consistent with
the barriers used for the workaround.
Change-Id: Ifc1d70b79cb5e0d87e90d88d376a59385667d338
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
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| f10644c5 | 13-Feb-2017 |
Antonio Nino Diaz <antonio.ninodiaz@arm.com> |
Improve debug output of the translation tables
The printed output has been improved in two ways:
- Whenever multiple invalid descriptors are found, only the first one
is printed, and a line is ad
Improve debug output of the translation tables
The printed output has been improved in two ways:
- Whenever multiple invalid descriptors are found, only the first one
is printed, and a line is added to inform about how many descriptors
have been omitted.
- At the beginning of each line there is an indication of the table
level the entry belongs to. Example of the new output:
`[LV3] VA:0x1000 PA:0x1000 size:0x1000 MEM-RO-S-EXEC`
Change-Id: Ib6f1cd8dbd449452f09258f4108241eb11f8d445
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
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