Until we get ZFS integrated into our boot loader, this is the next best
thing. The idea is simple - have a small FFS partition with a kernel,
modules and this ramdisk. Once the ramdisk boots it will mount the FFS
partition read only, copy the needed ZFS modules to the ramdisk and then
unmount the partition. Then we import the ZFS root pool, mount the
ZFS root filesystem and then pivot to it.
Because the initial FFS partition is not mounted at this point, we
can mount it in /altroot so we can replace the kernel and modules with
newer ones so it's easily maintainable.
This ZFS boot strapper currently makes the following assumptions:
* The device NAME=boot is the FFS with kernel, modules and this ramdisk.
* The ZFS root pool and root filesystem are called rpool/ROOT.
A boot.cfg menu entry can then be added like so:
menu=Boot ZFS root:fs /ramdisk-zfsroot.fs;boot
false positive with kMSan.
Here, LLVM reorders the conditions and checks 'vattr' before 'error'. But
if 'error' is non-zero then 'vattr' is not initialized, and kMSan notices
the uninitialized memory read.
to the number of channels supported by the hardware or less, if the hardware
supports multi channels.
- On monaural or stereo hardware, userland apps can always set 1ch or 2ch.
The kernel (audio layer) can convert mono-stereo each other.
- On 3ch (2.1ch) hardware, for example, userland apps can set 1, 2, or 3ch,
but not 4ch or more.
This allows userland apps to know actual number of channels supported by
the hardware in the same way as before.
PR kern/54973.
t_modctl.c:114:16, member access within misaligned address 0x71bf5bcede84
for type 'struct modstat_t'
t_modctl.c:116:13, load of misaligned address 0x7e81bc3c9104 for type
'struct modstat_t' which requires 8 byte alignment
t_builtin.c:174:16, member access within misaligned address 0x741271c25004
for type 'struct modstat_t'
t_builtin.c:175:4, member access within misaligned address 0x741271c251c4
for type 'struct modstat_t'
hash_page.c:792:2, left shift of 1 by 31 places cannot be represented in type 'int'
hash_page.c:855:2, left shift of 1 by 31 places cannot be represented in type 'int'
hash_page.c:779:3, left shift of 1 by 31 places cannot be represented in type 'int'
- Use lwz/stw instead of 4-byte lswi/stswi for 405 and later, which
support unaligned word load/store by hardware. In many cases, both
source and destination are aligned on word boundaries.
- Use dcbst instead of dcbf to flush cache. The former does not
invalidate the cache line. Copied data should be used soon after.
They are not used nor exposed externally in any header file; these
functions may have never been tested so far.
Enable them again when necessary.
Note that badaddr() for oea is used by macppc port, where it is
declared as an external function.
TLBF_USED. This should be originally intended behavior of this code
segment, because
- TLBF_USED is already checked just before, so marking this page
TLBF_USED is no-op.
- TLBF_REF flag exempts that page from being flushed from TLB in next
scan, when kernel stack may be still there with high probability.
to 2 in rev 1.29:
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/arch/powerpc/include/param.h#rev1.29
Since page size is 16KB on ibm4xx, USPACE is still 16KB, which is the
same size as on other powerpc processors.
This avoids kernel crash described in PR kern/54994. Also, even if the
PR is resolved, fork(2) easily fails with ENOMEM if UPAGES is 2, which
requires physically contiguous pages for u-area. No bad side effect is
observed as far as I can see.
XXX
Even with this commit, kern/54994 still critically affects other archs
with __HAVE_CPU_UAREA_ROUTINES, i.e., alpha, mips, powerpc/{oea,booke},
and riscv.
