On Tue, Sep 14, 2010 at 07:51:18PM +0200, matthieu castet wrote: > Hi, > > any feedback on that ? I was hoping to run your patch through a Xen guest. In the past modifications in that area caused unbootable kernels :-( But I am still suffering from post-vacation-amnesia and e-mails so haven't gotten to look at this. > > Thanks, > > Matthieu > > > matthieu castet a écrit : > > Note: this patch depends on "Correct improper large page > >preservation" patch > > This patch expands functionality of CONFIG_DEBUG_RODATA to set main > > (static) kernel data area as NX. > > The following steps are taken to achieve this: > > 1. Linker script is adjusted so .text always starts and ends on > >a page bound > > 2. Linker script is adjusted so .rodata always start and > > end on a page boundary > > 3. NX is set for all pages from _etext through _end in mark_rodata_ro. > > 4. free_init_pages() sets released memory NX in arch/x86/mm/init.c > > 5. bios rom is set to x when pcibios is used. > > The results of patch application may be observed in the diff > >of kernel page > > table dumps. > > pcibios : > > --- data_nx_pt_before.txt 2009-10-13 07:48:59.000000000 -0400 > > +++ data_nx_pt_after.txt 2009-10-13 07:26:46.000000000 -0400 > > @@ -2,8 +2,9 @@ > > 0x00000000-0xc0000000 3G pmd > > ---[ Kernel Mapping ]--- > > -0xc0000000-0xc0100000 1M RW GLB x pte > > +0xc0000000-0xc00a0000 640K RW GLB NX pte > > +0xc00a0000-0xc0100000 384K RW GLB x pte > > -0xc0100000-0xc03d7000 2908K ro GLB x pte > > +0xc0100000-0xc0318000 2144K ro GLB x pte > > +0xc0318000-0xc03d7000 764K ro GLB NX pte > > -0xc03d7000-0xc0600000 2212K RW GLB x pte > > +0xc03d7000-0xc0600000 2212K RW GLB NX pte > > 0xc0600000-0xf7a00000 884M RW PSE GLB NX pmd > > 0xf7a00000-0xf7bfe000 2040K RW GLB NX pte > > 0xf7bfe000-0xf7c00000 8K pte > > no pcibios : > > --- data_nx_pt_before.txt 2009-10-13 07:48:59.000000000 -0400 > > +++ data_nx_pt_after.txt 2009-10-13 07:26:46.000000000 -0400 > > @@ -2,8 +2,9 @@ > > 0x00000000-0xc0000000 3G pmd > > ---[ Kernel Mapping ]--- > > -0xc0000000-0xc0100000 1M RW GLB x pte > > +0xc0000000-0xc0100000 1M RW GLB NX pte > > -0xc0100000-0xc03d7000 2908K ro GLB x pte > > +0xc0100000-0xc0318000 2144K ro GLB x pte > > +0xc0318000-0xc03d7000 764K ro GLB NX pte > > -0xc03d7000-0xc0600000 2212K RW GLB x pte > > +0xc03d7000-0xc0600000 2212K RW GLB NX pte > > 0xc0600000-0xf7a00000 884M RW PSE GLB NX pmd > > 0xf7a00000-0xf7bfe000 2040K RW GLB NX pte > > 0xf7bfe000-0xf7c00000 8K pte > > The patch have been developed for Linux 2.6.34-rc2 x86 by > >Siarhei Liakh > > <sliakh.lkml@xxxxxxxxx> and Xuxian Jiang <jiang@xxxxxxxxxxx>. > > V1: initial patch for 2.6.30 > > V2: patch for 2.6.31-rc7 > > V3: moved all code into arch/x86, adjusted credits > > V4: fixed ifdef, removed credits from CREDITS > > V5: fixed an address calculation bug in mark_nxdata_nx() > > V6: added acked-by and PT dump diff to commit log > > V7: minor adjustments for -tip > > V8: rework with the merge of "Set first MB as RW+NX" > > Signed-off-by: Siarhei Liakh <sliakh.lkml@xxxxxxxxx> > > Signed-off-by: Xuxian Jiang <jiang@xxxxxxxxxxx> > > Signed-off-by: Matthieu CASTET <castet.matthieu@xxxxxxx> > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-next" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
