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arch-arm,mem: Don't hardcode secure mode accesses for semihosting (#1200)

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When accessing memory using functionalAccess(), the MMU could tell us to
use a nonsecure access even though the CPU is operating in secure mode.
I noticed this while trying to run a simple semihosting hello world with
the MMU+caches enabled and the semihosting calls ended up reading from
memory instead of the caches due to an S/NS mismatch.

See also https://github.com/gem5/gem5/pull/1198 which happens to also
mask the issue I saw, but I believe both changes are needed.

Change-Id: I9e6b9839b194fbd41938e2225449c74701ea7fee
This commit is contained in:
Alexander Richardson
2024-06-09 14:08:54 -07:00
committed by GitHub
parent 5cfad84a98
commit 3cfc550fc0
5 changed files with 71 additions and 62 deletions
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5
src/arch/arm/mmu.cc
View File

@@ -813,7 +813,8 @@ MMU::translateMmuOff(ThreadContext *tc, const RequestPtr &req, Mode mode,
// security state of the processor
if (state.isSecure)
req->setFlags(Request::SECURE);
else
req->clearFlags(Request::SECURE);
if (state.aarch64) {
bool selbit = bits(vaddr, 55);
TCR tcr1 = tc->readMiscReg(MISCREG_TCR_EL1);
@@ -917,6 +918,8 @@ MMU::translateMmuOn(ThreadContext* tc, const RequestPtr &req, Mode mode,
if (state.isSecure && !te->ns) {
req->setFlags(Request::SECURE);
} else {
req->clearFlags(Request::SECURE);
}
if (!is_fetch && fault == NoFault &&
(vaddr & mask(flags & AlignmentMask)) &&

4
src/arch/generic/mmu.cc
View File

@@ -149,8 +149,10 @@ BaseMMU::MMUTranslationGen::translate(Range &range) const
range.fault = mmu->translateFunctional(req, tc, mode);
if (range.fault == NoFault)
if (range.fault == NoFault) {
range.paddr = req->getPaddr();
range.flags = req->getFlags();
}
}
void

6
src/mem/translating_port_proxy.cc
View File

@@ -92,7 +92,7 @@ TranslatingPortProxy::tryReadBlob(Addr addr, void *p, uint64_t size) const
return tryOnBlob(mode, _tc->getMMUPtr()->translateFunctional(
addr, size, _tc, mode, flags),
[this, &p](const auto &range) {
PortProxy::readBlobPhys(range.paddr, flags, p, range.size);
PortProxy::readBlobPhys(range.paddr, range.flags, p, range.size);
p = static_cast<uint8_t *>(p) + range.size;
});
}
@@ -105,7 +105,7 @@ TranslatingPortProxy::tryWriteBlob(
return tryOnBlob(mode, _tc->getMMUPtr()->translateFunctional(
addr, size, _tc, mode, flags),
[this, &p](const auto &range) {
PortProxy::writeBlobPhys(range.paddr, flags, p, range.size);
PortProxy::writeBlobPhys(range.paddr, range.flags, p, range.size);
p = static_cast<const uint8_t *>(p) + range.size;
});
}
@@ -117,7 +117,7 @@ TranslatingPortProxy::tryMemsetBlob(Addr addr, uint8_t v, uint64_t size) const
return tryOnBlob(mode, _tc->getMMUPtr()->translateFunctional(
addr, size, _tc, mode, flags),
[this, v](const auto &range) {
PortProxy::memsetBlobPhys(range.paddr, flags, v, range.size);
PortProxy::memsetBlobPhys(range.paddr, range.flags, v, range.size);
});
}

3
src/mem/translation_gen.hh
View File

@@ -33,6 +33,7 @@
#include "base/logging.hh"
#include "base/types.hh"
#include "mem/request.hh"
namespace gem5
{
@@ -71,6 +72,8 @@ class TranslationGen
Addr size = 0;
Addr paddr = 0;
// PTEs can also set the Secure/non-secure bit, so it is stored here.
Request::Flags flags = 0;
Fault fault = NoFault;
};

115
src/mem/translation_gen.test.cc
View File

@@ -123,6 +123,7 @@ class TestTranslationGen : public TranslationGen
// If there wasn't a fault, size and paddr are meaningful.
range.size = resultPos->size;
range.paddr = resultPos->paddr;
range.flags = resultPos->flags;
}
// Advance to the next result.
resultPos++;
@@ -161,8 +162,8 @@ TEST(TranslationGen, SuccessfulTwoStep)
{
TestTranslationGen gen(0x10000, 0x10000, {
// Results for translate.
{0x0, 0x8000, 0x30000, NoFault},
{0x0, 0x8000, 0x40000, NoFault}
{0x0, 0x8000, 0x30000, {}, NoFault},
{0x0, 0x8000, 0x40000, {}, NoFault}
});
RangeList range_list;
@@ -171,15 +172,15 @@ TEST(TranslationGen, SuccessfulTwoStep)
// What the generator should return.
const RangeList expected_gen{
{0x10000, 0x8000, 0x30000, NoFault},
{0x18000, 0x8000, 0x40000, NoFault}
{0x10000, 0x8000, 0x30000, {}, NoFault},
{0x18000, 0x8000, 0x40000, {}, NoFault}
};
EXPECT_THAT(range_list, Pointwise(GenRangeEq(), expected_gen));
// What the generator should have been asked to translate.
const RangeList expected_trans{
{0x10000, 0x10000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault}
{0x10000, 0x10000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault}
};
EXPECT_THAT(gen.args, Pointwise(TransRangeEq(), expected_trans));
}
@@ -188,9 +189,9 @@ TEST(TranslationGen, RetryOnFault)
{
TestTranslationGen gen(0x10000, 0x10000, {
// Results for translate.
{0x0, 0x8000, 0x30000, NoFault},
{0x0, 0x0, 0x0, dummyFault1},
{0x0, 0x8000, 0x40000, NoFault}
{0x0, 0x8000, 0x30000, {}, NoFault},
{0x0, 0x0, 0x0, {}, dummyFault1},
{0x0, 0x8000, 0x40000, {}, NoFault}
});
RangeList range_list;
@@ -199,17 +200,17 @@ TEST(TranslationGen, RetryOnFault)
// What the generator should return.
const RangeList expected_gen{
{0x10000, 0x8000, 0x30000, NoFault},
{0x18000, 0x0, 0x0, dummyFault1},
{0x18000, 0x8000, 0x40000, NoFault}
{0x10000, 0x8000, 0x30000, {}, NoFault},
{0x18000, 0x0, 0x0, {}, dummyFault1},
{0x18000, 0x8000, 0x40000, {}, NoFault}
};
EXPECT_THAT(range_list, Pointwise(GenRangeEq(), expected_gen));
// What the generator should have been asked to translate.
const RangeList expected_trans{
{0x10000, 0x10000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault}
{0x10000, 0x10000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault}
};
EXPECT_THAT(gen.args, Pointwise(TransRangeEq(), expected_trans));
}
@@ -218,10 +219,10 @@ TEST(TranslationGen, RetryTwiceOnFault)
{
TestTranslationGen gen(0x10000, 0x10000, {
// Results for translate.
{0x0, 0x8000, 0x30000, NoFault},
{0x0, 0x0, 0x0, dummyFault1},
{0x0, 0x0, 0x0, dummyFault2},
{0x0, 0x8000, 0x40000, NoFault}
{0x0, 0x8000, 0x30000, {}, NoFault},
{0x0, 0x0, 0x0, {}, dummyFault1},
{0x0, 0x0, 0x0, {}, dummyFault2},
{0x0, 0x8000, 0x40000, {}, NoFault}
});
RangeList range_list;
@@ -230,19 +231,19 @@ TEST(TranslationGen, RetryTwiceOnFault)
// What the generator should return.
const RangeList expected_gen{
{0x10000, 0x8000, 0x30000, NoFault},
{0x18000, 0x0, 0x0, dummyFault1},
{0x18000, 0x0, 0x0, dummyFault2},
{0x18000, 0x8000, 0x40000, NoFault}
{0x10000, 0x8000, 0x30000, {}, NoFault},
{0x18000, 0x0, 0x0, {}, dummyFault1},
{0x18000, 0x0, 0x0, {}, dummyFault2},
{0x18000, 0x8000, 0x40000, {}, NoFault}
};
EXPECT_THAT(range_list, Pointwise(GenRangeEq(), expected_gen));
// What the generator should have been asked to translate.
const RangeList expected_trans{
{0x10000, 0x10000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault}
{0x10000, 0x10000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault}
};
EXPECT_THAT(gen.args, Pointwise(TransRangeEq(), expected_trans));
}
@@ -251,9 +252,9 @@ TEST(TranslationGen, FaultAtStart)
{
TestTranslationGen gen(0x10000, 0x10000, {
// Results for translate.
{0x0, 0x0, 0x0, dummyFault1},
{0x0, 0x8000, 0x30000, NoFault},
{0x0, 0x8000, 0x40000, NoFault}
{0x0, 0x0, 0x0, {}, dummyFault1},
{0x0, 0x8000, 0x30000, {}, NoFault},
{0x0, 0x8000, 0x40000, {}, NoFault}
});
RangeList range_list;
@@ -262,17 +263,17 @@ TEST(TranslationGen, FaultAtStart)
// What the generator should return.
const RangeList expected_gen{
{0x10000, 0x0, 0x0, dummyFault1},
{0x10000, 0x8000, 0x30000, NoFault},
{0x18000, 0x8000, 0x40000, NoFault}
{0x10000, 0x0, 0x0, {}, dummyFault1},
{0x10000, 0x8000, 0x30000, {}, NoFault},
{0x18000, 0x8000, 0x40000, {}, NoFault}
};
EXPECT_THAT(range_list, Pointwise(GenRangeEq(), expected_gen));
// What the generator should have been asked to translate.
const RangeList expected_trans{
{0x10000, 0x10000, 0x0, NoFault},
{0x10000, 0x10000, 0x0, NoFault},
{0x18000, 0x8000, 0x0, NoFault}
{0x10000, 0x10000, 0x0, {}, NoFault},
{0x10000, 0x10000, 0x0, {}, NoFault},
{0x18000, 0x8000, 0x0, {}, NoFault}
};
EXPECT_THAT(gen.args, Pointwise(TransRangeEq(), expected_trans));
}
@@ -281,10 +282,10 @@ TEST(TranslationGen, FaultInMiddle)
{
TestTranslationGen gen(0x10000, 0x18000, {
// Results for translate.
{0x0, 0x8000, 0x30000, NoFault},
{0x0, 0x0, 0x0, dummyFault1},
{0x0, 0x8000, 0x40000, NoFault},
{0x0, 0x8000, 0x50000, NoFault}
{0x0, 0x8000, 0x30000, {}, NoFault},
{0x0, 0x0, 0x0, {}, dummyFault1},
{0x0, 0x8000, 0x40000, {}, NoFault},
{0x0, 0x8000, 0x50000, {}, NoFault}
});
RangeList range_list;
@@ -293,19 +294,19 @@ TEST(TranslationGen, FaultInMiddle)
// What the generator should return.
const RangeList expected_gen{
{0x10000, 0x8000, 0x30000, NoFault},
{0x18000, 0x0, 0x0, dummyFault1},
{0x18000, 0x8000, 0x40000, NoFault},
{0x20000, 0x8000, 0x50000, NoFault}
{0x10000, 0x8000, 0x30000, {}, NoFault},
{0x18000, 0x0, 0x0, {}, dummyFault1},
{0x18000, 0x8000, 0x40000, {}, NoFault},
{0x20000, 0x8000, 0x50000, {}, NoFault}
};
EXPECT_THAT(range_list, Pointwise(GenRangeEq(), expected_gen));
// What the generator should have been asked to translate.
const RangeList expected_trans{
{0x10000, 0x18000, 0x0, NoFault},
{0x18000, 0x10000, 0x0, NoFault},
{0x18000, 0x10000, 0x0, NoFault},
{0x20000, 0x8000, 0x0, NoFault}
{0x10000, 0x18000, 0x0, {}, NoFault},
{0x18000, 0x10000, 0x0, {}, NoFault},
{0x18000, 0x10000, 0x0, {}, NoFault},
{0x20000, 0x8000, 0x0, {}, NoFault}
};
EXPECT_THAT(gen.args, Pointwise(TransRangeEq(), expected_trans));
}
@@ -314,9 +315,9 @@ TEST(TranslationGen, VariablePageSize)
{
TestTranslationGen gen(0x10000, 0x20000, {
// Results for translate.
{0x0, 0x8000, 0x30000, NoFault},
{0x0, 0x10000, 0x40000, NoFault},
{0x0, 0x8000, 0x50000, NoFault}
{0x0, 0x8000, 0x30000, {}, NoFault},
{0x0, 0x10000, 0x40000, {}, NoFault},
{0x0, 0x8000, 0x50000, {}, NoFault}
});
RangeList range_list;
@@ -325,17 +326,17 @@ TEST(TranslationGen, VariablePageSize)
// What the generator should return.
const RangeList expected_gen{
{0x10000, 0x8000, 0x30000, NoFault},
{0x18000, 0x10000, 0x40000, NoFault},
{0x28000, 0x8000, 0x50000, NoFault}
{0x10000, 0x8000, 0x30000, {}, NoFault},
{0x18000, 0x10000, 0x40000, {}, NoFault},
{0x28000, 0x8000, 0x50000, {}, NoFault}
};
EXPECT_THAT(range_list, Pointwise(GenRangeEq(), expected_gen));
// What the generator should have been asked to translate.
const RangeList expected_trans{
{0x10000, 0x20000, 0x0, NoFault},
{0x18000, 0x18000, 0x0, NoFault},
{0x28000, 0x8000, 0x0, NoFault}
{0x10000, 0x20000, 0x0, {}, NoFault},
{0x18000, 0x18000, 0x0, {}, NoFault},
{0x28000, 0x8000, 0x0, {}, NoFault}
};
EXPECT_THAT(gen.args, Pointwise(TransRangeEq(), expected_trans));
}