| Message ID | 20130807230856.GJ23053@n2100.arm.linux.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On Thu, Aug 08, 2013 at 12:08:56AM +0100, Russell King - ARM Linux wrote: > On Wed, Aug 07, 2013 at 10:05:21PM +0300, Aaro Koskinen wrote: > > On Wed, Aug 07, 2013 at 02:26:09AM +0300, Aaro Koskinen wrote: > > > I get the following on Amstrad Delta (E3) when booting unpatched > > > v3.11-rc4. The kernel config is after the crash. > > > > This is regression introduced between -rc3 and -rc4. According to the > > git bisect, the first bad commit is: > > > > commit e39e3f3ebfef03450cf7bfa7a974a8c61f7980c8 > > Author: Russell King <rmk+kernel@arm.linux.org.uk> > > Date: Tue Jul 9 01:03:17 2013 +0100 > > > > ARM: update FIQ support for relocation of vectors > > > > If I revert the commit from v3.11-rc4, the board boots fine. > > > > A. > > > > > Uncompressing Linux... done, booting the kernel. > > > [ 0.000000] Booting Linux on physical CPU 0x0 > > > [ 0.000000] Initializing cgroup subsys cpu > > > [ 0.000000] Linux version 3.11.0-rc4-e3 (aaro@blackmetal) (gcc version 4.7.3 (GCC) ) #4 PREEMPT Wed Aug 7 02:03:27 EEST 2013 > > > [ 0.000000] bootconsole [earlycon0] enabled > > > [ 0.000000] OMAP1510 > > > [ 0.000000] revision 2 handled as 15xx id: bc058c9b93111a16 > > Hmm, so ARM925T which is VIVT... > > > > [ 0.238868] Installing fiq handler from c001b110, length 0x164 > > > [ 0.245750] Unable to handle kernel paging request at virtual address ffff1224 > > In one way, that's good news - that's public independent proof that the > code associated with the vectors is well protected from kernel writes. :) > > Can you try this (untested) patch please? We need to write into this > page via the page's alias, rather than directly to it. Thanks. That seems to work - the board boots fine to shell as before. Feel free to add Reported-by: or Tested-by: from me to the patch. Thanks, A. > arch/arm/kernel/fiq.c | 8 ++------ > 1 files changed, 2 insertions(+), 6 deletions(-) > > diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c > index 25442f4..fc79202 100644 > --- a/arch/arm/kernel/fiq.c > +++ b/arch/arm/kernel/fiq.c > @@ -84,17 +84,13 @@ int show_fiq_list(struct seq_file *p, int prec) > > void set_fiq_handler(void *start, unsigned int length) > { > -#if defined(CONFIG_CPU_USE_DOMAINS) > - void *base = (void *)0xffff0000; > -#else > void *base = vectors_page; > -#endif > unsigned offset = FIQ_OFFSET; > > memcpy(base + offset, start, length); > + if (!cache_is_vipt_nonaliasing()) > + flush_icache_range(base + offset, offset + length); > flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length); > - if (!vectors_high()) > - flush_icache_range(offset, offset + length); > } > > int claim_fiq(struct fiq_handler *f) > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Thu, Aug 08, 2013 at 03:05:03AM +0300, Aaro Koskinen wrote: > That seems to work - the board boots fine to shell as before. Feel free > to add Reported-by: or Tested-by: from me to the patch. Thanks, done. Should be in linux-next by tomorrow.
diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c index 25442f4..fc79202 100644 --- a/arch/arm/kernel/fiq.c +++ b/arch/arm/kernel/fiq.c @@ -84,17 +84,13 @@ int show_fiq_list(struct seq_file *p, int prec) void set_fiq_handler(void *start, unsigned int length) { -#if defined(CONFIG_CPU_USE_DOMAINS) - void *base = (void *)0xffff0000; -#else void *base = vectors_page; -#endif unsigned offset = FIQ_OFFSET; memcpy(base + offset, start, length); + if (!cache_is_vipt_nonaliasing()) + flush_icache_range(base + offset, offset + length); flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length); - if (!vectors_high()) - flush_icache_range(offset, offset + length); } int claim_fiq(struct fiq_handler *f)