Re: [Qemu-devel] [PATCH] SVM IOIO intercept does not check all bits
On Fri, Dec 07, 2007 at 04:16:00PM +0100, Alexander Graf wrote: For IN/OUT instructions that access more than a single byte, the permission bits for all bytes are checked; if any bit is set to 1, the I/O operation is intercepted. That was the one. Thank you. Unfortunately there is another bug in this line. As there is only a single byte read from the permission bitmap, an unaligned 4-byte access to port 0x7 would be possible even when the access to port 0x8-0xa is not allowed. The updated patch fixes also this case. Bernhard Kauer Index: target-i386/helper.c === RCS file: /sources/qemu/qemu/target-i386/helper.c,v retrieving revision 1.95 diff -u -r1.95 helper.c --- target-i386/helper.c 18 Nov 2007 01:44:38 - 1.95 +++ target-i386/helper.c 8 Dec 2007 20:44:28 - @@ -4250,7 +4332,8 @@ uint64_t addr = ldq_phys(env-vm_vmcb + offsetof(struct vmcb, control.iopm_base_pa)); uint16_t port = (uint16_t) (param 16); -if(ldub_phys(addr + port / 8) (1 (port % 8))) +uint16_t mask = (1 ((param 4) 7)) - 1; +if(lduw_phys(addr + port / 8) (mask (port 7))) vmexit(type, param); } break;
Re: [Qemu-devel] [PATCH] SVM IOIO intercept does not check all bits
On Dec 7, 2007, at 3:20 PM, Bernhard Kauer wrote: On Fri, Dec 07, 2007 at 02:10:35PM +0100, Alexander Graf wrote: Could you please make this more readable? Not easy by a one liner. I splitted the mask calculation in a separate line. Is it better now? Much better, yes. Apart from that the patch is fine if the highest bit in the IOIO vector is to be set. I could not find that in the documentation. I did not understand your comment. Perhaps you mean the following sentence from the AMD vol. 2: I actually misread your patch, nevermind. For IN/OUT instructions that access more than a single byte, the permission bits for all bytes are checked; if any bit is set to 1, the I/O operation is intercepted. That was the one. Thank you. Greetings, Bernhard qemu_ioio.diff Looks good now (apart from whitespaces). Signed-off-by: Alexander Graf [EMAIL PROTECTED] Cheers, Alex
Re: [Qemu-devel] [PATCH] SVM IOIO intercept does not check all bits
Hi, On Dec 6, 2007, at 8:31 PM, Bernhard Kauer wrote: The SVM IOIO intercept does not check all bits in the IO permission map for in/outs with word or long operand size. The attached patch fix this. Bernhard Kauer qemu_ioio.diff Could you please make this more readable? Apart from that the patch is fine if the highest bit in the IOIO vector is to be set. I could not find that in the documentation. Cheers, Alex
Re: [Qemu-devel] [PATCH] SVM IOIO intercept does not check all bits
On Fri, Dec 07, 2007 at 02:10:35PM +0100, Alexander Graf wrote: Could you please make this more readable? Not easy by a one liner. I splitted the mask calculation in a separate line. Is it better now? Apart from that the patch is fine if the highest bit in the IOIO vector is to be set. I could not find that in the documentation. I did not understand your comment. Perhaps you mean the following sentence from the AMD vol. 2: For IN/OUT instructions that access more than a single byte, the permission bits for all bytes are checked; if any bit is set to 1, the I/O operation is intercepted. Greetings, Bernhard Index: target-i386/helper.c === RCS file: /sources/qemu/qemu/target-i386/helper.c,v retrieving revision 1.95 diff -u -r1.95 helper.c --- target-i386/helper.c 18 Nov 2007 01:44:38 - 1.95 +++ target-i386/helper.c 7 Dec 2007 14:10:57 - @@ -4250,7 +4331,8 @@ uint64_t addr = ldq_phys(env-vm_vmcb + offsetof(struct vmcb, control.iopm_base_pa)); uint16_t port = (uint16_t) (param 16); -if(ldub_phys(addr + port / 8) (1 (port % 8))) + uint8_t mask = (1 ((param 4) 0x7)) - 1; + if(ldub_phys(addr + port / 8) (mask (port % 8))) vmexit(type, param); } break;
