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Groups > linux.kernel > #1281274
| From | "H. Peter Anvin" <hpa@zytor.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH 1/6] x86: Add VMWare Host Communication Macros |
| Date | 2015-12-01 23:50 +0100 |
| Message-ID | <qB1Ue-7g2-7@gated-at.bofh.it> (permalink) |
| References | <qB1rb-76P-3@gated-at.bofh.it> <qB1rb-76P-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On 12/01/15 14:18, Sinclair Yeh wrote:
> These macros will be used by multiple VMWare modules for handling
> host communication.
> + __asm__ __volatile__ ("inl %%dx" : \
This is odd at best; the standard assembly form of this instruction is:
inl (%dx),%eax
Also, we don't need the underscored forms of asm and volatile for kernel
code.
> + __asm__ __volatile__ ("movq %13, %%rbp;" \
> + "cld; rep outsb; " \
> + "movq %%rbp, %6" : \
cld shouldn't be necessary here, DF=0 is part of the normal ABI environment.
You also don't save/restore %rbp here, but you do below? Seems very odd.
It might be better do so something like:
+#define VMW_PORT_HB_OUT(in1, in2, port_num, magic, \
+ eax, ebx, ecx, edx, si, di, bp) \
+({ \
+ __asm__ __volatile__ ("xchgq %6, %%rbp;" \
+ "cld; rep outsb; " \
+ "xchgq %%rbp, %6" : \
+ "=a"(eax), \
+ "=b"(ebx), \
+ "=c"(ecx), \
+ "=d"(edx), \
+ "+S"(si), \
+ "+D"(di), \
+ "+r"(bp) : \
+ "a"(magic), \
+ "b"(in1), \
+ "c"(in2), \
+ "d"(port_num) : \
+ "memory", "cc"); \
+})
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[PATCH 1/6] x86: Add VMWare Host Communication Macros "Sinclair Yeh" <syeh@vmware.com> - 2015-12-01 23:20 +0100
[PATCH 2/6] x86: Update vmware.c to use the common VMW_PORT macros "Sinclair Yeh" <syeh@vmware.com> - 2015-12-01 23:20 +0100
[PATCH 6/6] VMware balloon: Update vmw_balloon.c to use the VMW_PORT macro "Sinclair Yeh" <syeh@vmware.com> - 2015-12-01 23:20 +0100
Re: [PATCH 6/6] VMware balloon: Update vmw_balloon.c to use the VMW_PORT macro Xavier Deguillard <xdeguillard@vmware.com> - 2015-12-01 23:40 +0100
Re: [PATCH 6/6] VMware balloon: Update vmw_balloon.c to use the VMW_PORT macro "Sinclair Yeh" <syeh@vmware.com> - 2015-12-02 00:20 +0100
Re: [PATCH 1/6] x86: Add VMWare Host Communication Macros Xavier Deguillard <xdeguillard@vmware.com> - 2015-12-01 23:40 +0100
Re: [PATCH 1/6] x86: Add VMWare Host Communication Macros "H. Peter Anvin" <hpa@zytor.com> - 2015-12-01 23:50 +0100
Re: [PATCH 1/6] x86: Add VMWare Host Communication Macros "Sinclair Yeh" <syeh@vmware.com> - 2015-12-04 23:40 +0100
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