[bios] Make uses of REAL_CODE() and PHYS_CODE() 64-bit clean
On a 64-bit CPU, any modification of a register by 32-bit or 16-bit code will destroy the invisible upper 32 bits of the corresponding 64-bit register. For example: a 32-bit "pushl %eax" followed by a "popl %eax" will zero the upper half of %rax. This differs from the treatment of upper halves of 32-bit registers by 16-bit code: a "pushw %ax" followed by a "popw %ax" will leave the upper 16 bits of %eax unmodified. Inline assembly generated using REAL_CODE() or PHYS_CODE() will therefore have to preserve the upper halves of all registers, to avoid clobbering registers that gcc expects to be preserved. Output operands from REAL_CODE() and PHYS_CODE() assembly may therefore contain undefined values in the upper 32 bits. Fix by using explicit variable widths (e.g. uint32_t) for non-discarded output operands, to ensure that undefined values in the upper 32 bits of 64-bit registers are ignored. Signed-off-by: Michael Brown <mcb30@ipxe.org>
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@ -241,7 +241,7 @@ static int nbi_process_segments ( struct image *image,
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*/
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static int nbi_boot16 ( struct image *image, struct imgheader *imgheader ) {
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int discard_D, discard_S, discard_b;
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int rc;
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int32_t rc;
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DBGC ( image, "NBI %p executing 16-bit image at %04x:%04x\n", image,
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imgheader->execaddr.segoff.segment,
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@ -283,7 +283,7 @@ static int nbi_boot32 ( struct image *image, struct imgheader *imgheader ) {
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0
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};
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int discard_D, discard_S, discard_b;
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int rc;
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int32_t rc;
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DBGC ( image, "NBI %p executing 32-bit image at %lx\n",
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image, imgheader->execaddr.linear );
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@ -174,7 +174,7 @@ static int meme820 ( struct memory_map *memmap ) {
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struct memory_region *prev_region = NULL;
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uint32_t next = 0;
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uint32_t smap;
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size_t size;
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uint32_t size;
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unsigned int flags;
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unsigned int discard_D;
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@ -216,7 +216,7 @@ static int meme820 ( struct memory_map *memmap ) {
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}
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if ( size < E820_MIN_SIZE ) {
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DBG ( "INT 15,e820 returned only %zd bytes\n", size );
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DBG ( "INT 15,e820 returned only %d bytes\n", size );
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return -EINVAL;
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}
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@ -70,7 +70,7 @@ static int pcibios_num_bus ( void ) {
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*/
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int pcibios_read ( struct pci_device *pci, uint32_t command, uint32_t *value ){
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int discard_b, discard_D;
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int status;
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uint16_t status;
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__asm__ __volatile__ ( REAL_CODE ( "stc\n\t"
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"int $0x1a\n\t"
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@ -85,7 +85,7 @@ int pcibios_read ( struct pci_device *pci, uint32_t command, uint32_t *value ){
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"b" ( pci->busdevfn )
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: "edx" );
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return ( ( status >> 8 ) & 0xff );
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return ( status >> 8 );
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}
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/**
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@ -98,7 +98,7 @@ int pcibios_read ( struct pci_device *pci, uint32_t command, uint32_t *value ){
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*/
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int pcibios_write ( struct pci_device *pci, uint32_t command, uint32_t value ){
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int discard_b, discard_c, discard_D;
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int status;
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uint16_t status;
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__asm__ __volatile__ ( REAL_CODE ( "stc\n\t"
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"int $0x1a\n\t"
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@ -111,7 +111,7 @@ int pcibios_write ( struct pci_device *pci, uint32_t command, uint32_t value ){
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"b" ( pci->busdevfn ), "c" ( value )
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: "edx" );
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return ( ( status >> 8 ) & 0xff );
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return ( status >> 8 );
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}
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PROVIDE_PCIAPI ( pcbios, pci_num_bus, pcibios_num_bus );
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@ -187,7 +187,7 @@ uint8_t rtc_sample ( void ) {
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/* Disable interrupts */
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"cli\n\t"
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)
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: "=a" ( after ), "=d" ( before ), "=q" ( temp )
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: "=a" ( after ), "=d" ( before ), "=Q" ( temp )
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: "2" ( 0 ) );
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return ( after - before );
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@ -208,8 +208,10 @@ int pxeparent_call ( SEGOFF16_t entry, unsigned int function,
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void *params, size_t params_len ) {
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struct pxeparent_profiler *profiler = pxeparent_profiler ( function );
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PXENV_EXIT_t exit;
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unsigned long started;
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unsigned long stopped;
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uint32_t before;
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uint32_t started;
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uint32_t stopped;
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uint32_t after;
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int discard_D;
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int rc;
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@ -240,12 +242,14 @@ int pxeparent_call ( SEGOFF16_t entry, unsigned int function,
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"D" ( __from_data16 ( &pxeparent_params ) )
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: "ecx", "esi" );
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profile_stop ( &profiler->total );
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profile_start_at ( &profiler->p2r, profile_started ( &profiler->total));
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before = profile_started ( &profiler->total );
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after = profile_stopped ( &profiler->total );
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profile_start_at ( &profiler->p2r, before );
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profile_stop_at ( &profiler->p2r, started );
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profile_start_at ( &profiler->ext, started );
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profile_stop_at ( &profiler->ext, stopped );
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profile_start_at ( &profiler->r2p, stopped );
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profile_stop_at ( &profiler->r2p, profile_stopped ( &profiler->total ));
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profile_stop_at ( &profiler->r2p, after );
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/* Determine return status code based on PXENV_EXIT and
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* PXENV_STATUS
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