kdump on ARM

[M. Warner Losh]

In message: <6c36ec371002170654n5e441c6eib9a8c9aad61c1e87 at mail.gmail.com>
            batcilla itself <batcilla at gmail.com> writes:
: 2010/2/17 Hans Petter Selasky <hselasky at c2i.net>
: >
: > On Wednesday 17 February 2010 15:18:12 Grzegorz Bernacki wrote:
: > > Hi,
: > >
: > > I've noticed that kdump on ARM doesn't work properly, it generates bus
: > >  error. The problem is that structures dumped into ktrace.out are not
: > >  aligned. Processing such a structure causes Aligment Fault. One solution
: > >  is to copy structure into local variable and then process it, please see
: > >  patch below. But I am not sure if this is the best solution and maybe
: > >  someone has a better idea.
: > >
: > > grzesiek
: > >
: > >
: > > diff --git a/usr.bin/kdump/kdump.c b/usr.bin/kdump/kdump.c
: > > index 386221e..5a15886 100644
: > > --- a/usr.bin/kdump/kdump.c
: > > +++ b/usr.bin/kdump/kdump.c
: > > @@ -1325,6 +1325,10 @@ ktrstat(struct stat *statp)
: > >   void
: > >   ktrstruct(char *buf, size_t buflen)
: > >   {
: > > +#if defined(__arm__)
: > > +       struct stat stat;
: > > +       struct sockaddr sockaddr;
: > > +#endif
: > >          char *name, *data;
: > >          size_t namelen, datalen;
: > >          int i;
: > > @@ -1348,12 +1352,22 @@ ktrstruct(char *buf, size_t buflen)
: > >          if (strcmp(name, "stat") == 0) {
: > >                  if (datalen != sizeof(struct stat))
: > >                          goto invalid;
: > > +#if defined(__arm__)
: > > +               memcpy(&stat, data, sizeof(struct stat));
: > > +               ktrstat(&stat);
: > > +#else
: > >                  ktrstat((struct stat *)data);
: > > +#endif
: > >          } else if (strcmp(name, "sockaddr") == 0) {
: > >                  if (datalen < sizeof(struct sockaddr) ||
: > >                      datalen != ((struct sockaddr *)(data))->sa_len)
: > >                          goto invalid;
: > > +#if defined(__arm__)
: > > +               memcpy(&sockaddr, data, sizeof(struct sockaddr));
: > > +               ktrsockaddr(&sockaddr);
: > > +#else
: > >                  ktrsockaddr((struct sockaddr *)data);
: > > +#endif
: > >          } else {
: > >                  printf("unknown structure\n");
: > >          }
: >
: > I think more than ARM is affected by this.
: >
: > --HPS
: ARM affected definitely, just today had that Align error with -current
: while tried to use ng_bridge with wlan0

Where exactly was the error?  Do you have a traceback?

Warner