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author | Zejun Wu <watashi@fb.com> | 2018-12-28 20:37:13 -0800 |
---|---|---|
committer | Ben Gamari <ben@smart-cactus.org> | 2019-01-30 10:06:32 -0500 |
commit | e29b1ee72d77d5a06ac949f9dcc80108243a25c0 (patch) | |
tree | 3c2104b52c52d77b130c98d3cd486eb47ed2f347 /rts/linker/SymbolExtras.c | |
parent | 4bf35da4fccd2a21153a1c19bfa80006e99e02a1 (diff) | |
download | haskell-e29b1ee72d77d5a06ac949f9dcc80108243a25c0.tar.gz |
Add a RTS option -xp to load PIC object anywhere in address space
Summary:
This re-applies {D5195} with fixes for i386:
* Fix unused label warnings, see {D5230} or {D5273}
* Fix a silly bug introduced by moving `#if`
{P190}
Add a RTS option -xp to load PIC object anywhere in address space. We do
this by relaxing the requirement of <0x80000000 result of
`mmapForLinker` and implying USE_CONTIGUOUS_MMAP.
We also need to change calls to `ocInit` and `ocGetNames` to avoid
dangling pointers when the address of `oc->image` is changed by
`ocAllocateSymbolExtra`.
Test Plan:
See {D5195}, also test under i386:
```
$ uname -a
Linux watashi-arch32 4.18.5-arch1-1.0-ARCH #1 SMP PREEMPT Tue Aug 28
20:45:30 CEST 2018 i686 GNU/Linux
$ cd testsuite/tests/th/ && make test
...
```
will run `./validate` on stacked diff.
Reviewers: simonmar, bgamari, alpmestan, trommler, hvr, erikd
Reviewed By: simonmar
Subscribers: rwbarton, carter
Differential Revision: https://phabricator.haskell.org/D5289
Diffstat (limited to 'rts/linker/SymbolExtras.c')
-rw-r--r-- | rts/linker/SymbolExtras.c | 61 |
1 files changed, 39 insertions, 22 deletions
diff --git a/rts/linker/SymbolExtras.c b/rts/linker/SymbolExtras.c index 88541f44d0..4c40b10877 100644 --- a/rts/linker/SymbolExtras.c +++ b/rts/linker/SymbolExtras.c @@ -19,6 +19,12 @@ #include "linker/SymbolExtras.h" #include "linker/M32Alloc.h" +#if defined(OBJFORMAT_ELF) +# include "linker/Elf.h" +#elif defined(OBJFORMAT_MACHO) +# include "linker/MachO.h" +#endif + #include <string.h> #if RTS_LINKER_USE_MMAP #include <sys/mman.h> @@ -46,8 +52,24 @@ int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first ) { size_t n; + void* oldImage = oc->image; + + if (count > 0) { + if (!RTS_LINKER_USE_MMAP) { + + // round up to the nearest 4 + int aligned = (oc->fileSize + 3) & ~3; + int misalignment = oc->misalignment; - if (RTS_LINKER_USE_MMAP && USE_CONTIGUOUS_MMAP) { + oc->image -= misalignment; + oc->image = stgReallocBytes( oc->image, + misalignment + + aligned + sizeof (SymbolExtra) * count, + "ocAllocateSymbolExtras" ); + oc->image += misalignment; + + oc->symbol_extras = (SymbolExtra *) (oc->image + aligned); + } else if (USE_CONTIGUOUS_MMAP || RtsFlags.MiscFlags.linkerAlwaysPic) { n = roundUpToPage(oc->fileSize); /* Keep image and symbol_extras contiguous */ @@ -63,42 +85,37 @@ int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first ) oc->imageMapped = true; oc->fileSize = n + (sizeof(SymbolExtra) * count); oc->symbol_extras = (SymbolExtra *) (oc->image + n); - if(mprotect(new, allocated_size, PROT_READ | PROT_EXEC) != 0) { - sysErrorBelch("unable to protect memory"); + if (mprotect(new, allocated_size, + PROT_READ | PROT_WRITE | PROT_EXEC) != 0) { + sysErrorBelch("unable to protect memory"); } } else { oc->symbol_extras = NULL; return 0; } - } - else if( count > 0 ) { - if (RTS_LINKER_USE_MMAP) { - n = roundUpToPage(oc->fileSize); - + } else { oc->symbol_extras = m32_alloc(sizeof(SymbolExtra) * count, 8); if (oc->symbol_extras == NULL) return 0; } - else { - // round up to the nearest 4 - int aligned = (oc->fileSize + 3) & ~3; - int misalignment = oc->misalignment; - - oc->image -= misalignment; - oc->image = stgReallocBytes( oc->image, - misalignment + - aligned + sizeof (SymbolExtra) * count, - "ocAllocateSymbolExtras" ); - oc->image += misalignment; - - oc->symbol_extras = (SymbolExtra *) (oc->image + aligned); - } } if (oc->symbol_extras != NULL) { memset( oc->symbol_extras, 0, sizeof (SymbolExtra) * count ); } + // ObjectCodeFormatInfo contains computed addresses based on offset to + // image, if the address of image changes, we need to invalidate + // the ObjectCodeFormatInfo and recompute it. + if (oc->image != oldImage) { +#if defined(OBJFORMAT_MACHO) + ocInit_MachO( oc ); +#endif +#if defined(OBJFORMAT_ELF) + ocInit_ELF( oc ); +#endif + } + oc->first_symbol_extra = first; oc->n_symbol_extras = count; |