Re: [PATCH] KVM: 'asm' operand has impossible constraints
S.Çağlar Onur wrote: 27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı: The patch looks correct, but I don't understand the gcc error message. Are we sure this isn't a gcc 4.2 bug? "g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free to use "r" or "m", no? Accorgind to GCC devs. its not a bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the problem described like; "g" means "r"+"i" so the register allocator in the -O0 case is selecting "r" while in the optimize case is selecting "i" That's a different bug. The gcc PR has an assembler error message, as expected, whereas the kvm miscompile has a compiler error, which I don't understand. Anyhow, your patch is correct (because selecting "i" is indeed erroneous) so I'll apply it, but I'm worried that there's a gcc bug in there that we ought to report. -- error compiling committee.c: too many arguments to function - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
Paweł Sikora wrote:
On Saturday 27 of January 2007 10:05:53 Avi Kivity wrote:
"g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free
to use "r" or "m", no?
`r'
A register operand is allowed provided that it is in a general
register.
`g'
Any register, memory or immediate integer operand is allowed,
except for registers that are not general registers.
so, it looks like g == !r for registers ( not general vs. general regs ).
I read it as g == !!r for registers ("except" and "not" constitute a
double negative).
--
error compiling committee.c: too many arguments to function
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Re: [PATCH] KVM: 'asm' operand has impossible constraints
S.Çağlar Onur wrote: "g" means "r"+"i" so the register allocator in the -O0 case is selecting "r" while in the optimize case is selecting "i" "g" means "rmi", not "ri". -hpa - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
S.Çağlar Onur wrote: g means r+i so the register allocator in the -O0 case is selecting r while in the optimize case is selecting i g means rmi, not ri. -hpa - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
Paweł Sikora wrote: On Saturday 27 of January 2007 10:05:53 Avi Kivity wrote: g appears to be equivalent to rmi, if i is impossible, gcc is free to use r or m, no? `r' A register operand is allowed provided that it is in a general register. `g' Any register, memory or immediate integer operand is allowed, except for registers that are not general registers. so, it looks like g == !r for registers ( not general vs. general regs ). I read it as g == !!r for registers (except and not constitute a double negative). -- error compiling committee.c: too many arguments to function - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
S.Çağlar Onur wrote: 27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı: The patch looks correct, but I don't understand the gcc error message. Are we sure this isn't a gcc 4.2 bug? g appears to be equivalent to rmi, if i is impossible, gcc is free to use r or m, no? Accorgind to GCC devs. its not a bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the problem described like; g means r+i so the register allocator in the -O0 case is selecting r while in the optimize case is selecting i That's a different bug. The gcc PR has an assembler error message, as expected, whereas the kvm miscompile has a compiler error, which I don't understand. Anyhow, your patch is correct (because selecting i is indeed erroneous) so I'll apply it, but I'm worried that there's a gcc bug in there that we ought to report. -- error compiling committee.c: too many arguments to function - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
On Saturday 27 January 2007 16:28, S.Çağlar Onur wrote: > 27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı: > > The patch looks correct, but I don't understand the gcc error message. > > Are we sure this isn't a gcc 4.2 bug? > > > > "g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free > > to use "r" or "m", no? > > Accorgind to GCC devs. its not a bug > (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the > problem described like; > > "g" means "r"+"i" so the register allocator in the -O0 case is selecting > "r" while in the optimize case is selecting "i" Sounds like a bug to me! After all, shouldn't the different sections of code be selecting the *same* bits ? DRH - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı: > The patch looks correct, but I don't understand the gcc error message. > Are we sure this isn't a gcc 4.2 bug? > > "g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free > to use "r" or "m", no? Accorgind to GCC devs. its not a bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the problem described like; "g" means "r"+"i" so the register allocator in the -O0 case is selecting "r" while in the optimize case is selecting "i" -- S.Çağlar Onur <[EMAIL PROTECTED]> http://cekirdek.pardus.org.tr/~caglar/ Linux is like living in a teepee. No Windows, no Gates and an Apache in house! pgpFqCCG4LPCh.pgp Description: PGP signature
Re: [PATCH] KVM: 'asm' operand has impossible constraints
On Saturday 27 of January 2007 10:05:53 Avi Kivity wrote: > "g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free > to use "r" or "m", no? `r' A register operand is allowed provided that it is in a general register. `g' Any register, memory or immediate integer operand is allowed, except for registers that are not general registers. so, it looks like g == !r for registers ( not general vs. general regs ). - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
S.Çağlar Onur wrote:
Hi;
-rc6 fails with latest gcc 4.2 snapshot as following;
CC [M] drivers/kvm/svm.o
drivers/kvm/svm.c:206: warning: 'inject_db' defined but not used
drivers/kvm/svm.c: In function 'svm_vcpu_run':
drivers/kvm/kvm.h:560: error: 'asm' operand has impossible constraints
make[2]: *** [drivers/kvm/svm.o] Error 1
make[1]: *** [drivers/kvm] Error 2
make: *** [drivers] Error 2
And according to this thread http://lkml.org/lkml/2006/11/11/129, solution is
converting g to rm, patch follows
The patch looks correct, but I don't understand the gcc error message.
Are we sure this isn't a gcc 4.2 bug?
"g" appears to be equivalent to "rmi", if "i" is impossible, gcc is free
to use "r" or "m", no?
Signed-off-by: S.Çağlar Onur <[EMAIL PROTECTED]>
Index: linux-2.6/drivers/kvm/kvm.h
===
--- linux-2.6.orig/drivers/kvm/kvm.h2007-01-26 01:38:35.0 +0200
+++ linux-2.6/drivers/kvm/kvm.h 2007-01-26 01:37:48.0 +0200
@@ -557,7 +557,7 @@
#ifndef load_ldt
static inline void load_ldt(u16 sel)
{
- asm ("lldt %0" : : "g"(sel));
+ asm ("lldt %0" : : "rm"(sel));
}
#endif
--
Do not meddle in the internals of kernels, for they are subtle and quick to
panic.
-
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the body of a message to [EMAIL PROTECTED]
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Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
S.Çağlar Onur wrote:
Hi;
-rc6 fails with latest gcc 4.2 snapshot as following;
CC [M] drivers/kvm/svm.o
drivers/kvm/svm.c:206: warning: 'inject_db' defined but not used
drivers/kvm/svm.c: In function 'svm_vcpu_run':
drivers/kvm/kvm.h:560: error: 'asm' operand has impossible constraints
make[2]: *** [drivers/kvm/svm.o] Error 1
make[1]: *** [drivers/kvm] Error 2
make: *** [drivers] Error 2
And according to this thread http://lkml.org/lkml/2006/11/11/129, solution is
converting g to rm, patch follows
The patch looks correct, but I don't understand the gcc error message.
Are we sure this isn't a gcc 4.2 bug?
g appears to be equivalent to rmi, if i is impossible, gcc is free
to use r or m, no?
Signed-off-by: S.Çağlar Onur [EMAIL PROTECTED]
Index: linux-2.6/drivers/kvm/kvm.h
===
--- linux-2.6.orig/drivers/kvm/kvm.h2007-01-26 01:38:35.0 +0200
+++ linux-2.6/drivers/kvm/kvm.h 2007-01-26 01:37:48.0 +0200
@@ -557,7 +557,7 @@
#ifndef load_ldt
static inline void load_ldt(u16 sel)
{
- asm (lldt %0 : : g(sel));
+ asm (lldt %0 : : rm(sel));
}
#endif
--
Do not meddle in the internals of kernels, for they are subtle and quick to
panic.
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
On Saturday 27 of January 2007 10:05:53 Avi Kivity wrote: g appears to be equivalent to rmi, if i is impossible, gcc is free to use r or m, no? `r' A register operand is allowed provided that it is in a general register. `g' Any register, memory or immediate integer operand is allowed, except for registers that are not general registers. so, it looks like g == !r for registers ( not general vs. general regs ). - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] KVM: 'asm' operand has impossible constraints
27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı: The patch looks correct, but I don't understand the gcc error message. Are we sure this isn't a gcc 4.2 bug? g appears to be equivalent to rmi, if i is impossible, gcc is free to use r or m, no? Accorgind to GCC devs. its not a bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the problem described like; g means r+i so the register allocator in the -O0 case is selecting r while in the optimize case is selecting i -- S.Çağlar Onur [EMAIL PROTECTED] http://cekirdek.pardus.org.tr/~caglar/ Linux is like living in a teepee. No Windows, no Gates and an Apache in house! pgpFqCCG4LPCh.pgp Description: PGP signature
Re: [PATCH] KVM: 'asm' operand has impossible constraints
On Saturday 27 January 2007 16:28, S.Çağlar Onur wrote: 27 Oca 2007 Cts tarihinde, Avi Kivity şunları yazmıştı: The patch looks correct, but I don't understand the gcc error message. Are we sure this isn't a gcc 4.2 bug? g appears to be equivalent to rmi, if i is impossible, gcc is free to use r or m, no? Accorgind to GCC devs. its not a bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29808), on comment #5 the problem described like; g means r+i so the register allocator in the -O0 case is selecting r while in the optimize case is selecting i Sounds like a bug to me! After all, shouldn't the different sections of code be selecting the *same* bits ? DRH - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH] KVM: 'asm' operand has impossible constraints
Hi;
-rc6 fails with latest gcc 4.2 snapshot as following;
CC [M] drivers/kvm/svm.o
drivers/kvm/svm.c:206: warning: 'inject_db' defined but not used
drivers/kvm/svm.c: In function 'svm_vcpu_run':
drivers/kvm/kvm.h:560: error: 'asm' operand has impossible constraints
make[2]: *** [drivers/kvm/svm.o] Error 1
make[1]: *** [drivers/kvm] Error 2
make: *** [drivers] Error 2
And according to this thread http://lkml.org/lkml/2006/11/11/129, solution is
converting g to rm, patch follows
Signed-off-by: S.Çağlar Onur <[EMAIL PROTECTED]>
Index: linux-2.6/drivers/kvm/kvm.h
===
--- linux-2.6.orig/drivers/kvm/kvm.h2007-01-26 01:38:35.0 +0200
+++ linux-2.6/drivers/kvm/kvm.h 2007-01-26 01:37:48.0 +0200
@@ -557,7 +557,7 @@
#ifndef load_ldt
static inline void load_ldt(u16 sel)
{
- asm ("lldt %0" : : "g"(sel));
+ asm ("lldt %0" : : "rm"(sel));
}
#endif
--
S.Çağlar Onur <[EMAIL PROTECTED]>
http://cekirdek.pardus.org.tr/~caglar/
Linux is like living in a teepee. No Windows, no Gates and an Apache in house!
pgp6Vpq3XRuCJ.pgp
Description: PGP signature
[PATCH] KVM: 'asm' operand has impossible constraints
Hi;
-rc6 fails with latest gcc 4.2 snapshot as following;
CC [M] drivers/kvm/svm.o
drivers/kvm/svm.c:206: warning: 'inject_db' defined but not used
drivers/kvm/svm.c: In function 'svm_vcpu_run':
drivers/kvm/kvm.h:560: error: 'asm' operand has impossible constraints
make[2]: *** [drivers/kvm/svm.o] Error 1
make[1]: *** [drivers/kvm] Error 2
make: *** [drivers] Error 2
And according to this thread http://lkml.org/lkml/2006/11/11/129, solution is
converting g to rm, patch follows
Signed-off-by: S.Çağlar Onur [EMAIL PROTECTED]
Index: linux-2.6/drivers/kvm/kvm.h
===
--- linux-2.6.orig/drivers/kvm/kvm.h2007-01-26 01:38:35.0 +0200
+++ linux-2.6/drivers/kvm/kvm.h 2007-01-26 01:37:48.0 +0200
@@ -557,7 +557,7 @@
#ifndef load_ldt
static inline void load_ldt(u16 sel)
{
- asm (lldt %0 : : g(sel));
+ asm (lldt %0 : : rm(sel));
}
#endif
--
S.Çağlar Onur [EMAIL PROTECTED]
http://cekirdek.pardus.org.tr/~caglar/
Linux is like living in a teepee. No Windows, no Gates and an Apache in house!
pgp6Vpq3XRuCJ.pgp
Description: PGP signature
