diff options
| -rw-r--r-- | chapter01/changelog.xml | 9 | ||||
| -rw-r--r-- | chapter08/pkgmgt.xml | 15 | ||||
| -rw-r--r-- | chapter08/strippingagain.xml | 66 |
3 files changed, 74 insertions, 16 deletions
diff --git a/chapter01/changelog.xml b/chapter01/changelog.xml index 487b9e01d..8a3807262 100644 --- a/chapter01/changelog.xml +++ b/chapter01/changelog.xml @@ -47,6 +47,15 @@ <para>2021-07-25</para> <itemizedlist> <listitem> + <para>[xry111] - (Hopefully) complete stripping workaround.</para> + </listitem> + </itemizedlist> + </listitem> + + <listitem> + <para>2021-07-25</para> + <itemizedlist> + <listitem> <para>[bdubbs] - Add workaround to strip libraries correctly.</para> </listitem> diff --git a/chapter08/pkgmgt.xml b/chapter08/pkgmgt.xml index 228a13378..43b9c57d3 100644 --- a/chapter08/pkgmgt.xml +++ b/chapter08/pkgmgt.xml @@ -121,6 +121,21 @@ and rerun that command to confirm nothing is still using the deleted libraries. </para></listitem> + + <listitem> + <para>If a binary or a shared library is overwrote, the processes + using the code or data in the binary or library may crash. The + correct way to update a binary or a shared library without causing + the process to crash is: remove it first, then install the new + version into position. The <command>install</command> command + provided by <application>Coreutils</application> has already + implemented this and most packages use it to install binaries and + libraries. So you won't be troubled by this issue most of the time. + However, the install process of some packages (notably Mozilla JS + in BLFS) just overwrites the file if it exists and causes crash, so + it's safer to save your work and close unneeded running processes + before updating a package.</para> + </listitem> </itemizedlist> </sect2> diff --git a/chapter08/strippingagain.xml b/chapter08/strippingagain.xml index d2e686e8f..e663f2d8e 100644 --- a/chapter08/strippingagain.xml +++ b/chapter08/strippingagain.xml @@ -23,18 +23,28 @@ <command>strip</command> commands, it is a good idea to make a backup of the LFS system in its current state.</para> - <para>First place the debugging symbols for selected libraries - in separate files. This debugging information is needed if running + <para>The debugging symbols for selected libraries are placed + in separate files. These debugging information is needed if running regression tests that use <ulink url='&blfs-book;/general/valgrind.html'>valgrind</ulink> or <ulink url='&blfs-book;/general/gdb.html'>gdb</ulink> later in BLFS. </para> + <para>And, <command>strip</command> will overwrite the binary or library + file. This may crash the processes using code or data from the file. If + the process running <command>strip</command> itself is affected, the + binary or library being stripped may be destroyed. This may make the + system completely unusable. To avoid it, we'll copy some libraries and + binaries into <filename class="directory">/tmp</filename>, strip them + there, and install them back with the <command>install</command> command. + Read the related entry in <xref linkend="pkgmgmt-upgrade-issues"/> for the + rationale to use the <command>install</command> command here.</para> + <!-- also of interest are libgfortan, libgo, libgomp, and libobjc from GCC --> <!--<screen><userinput>save_lib="ld-2.25.so libc-2.25.so libpthread-2.25.so libthread_db-1.0.so"--> <screen><userinput>save_usrlib="ld-&glibc-version;.so libc-&glibc-version;.so libpthread-&glibc-version;.so libthread_db-&libthread_db-version;.so - libquadmath.so.&libquadmath-version; libstdc++.so.&libstdcpp-version; libz.so.&zlib-version; + libquadmath.so.&libquadmath-version; libstdc++.so.&libstdcpp-version; libitm.so.&libitm-version; libatomic.so.&libatomic-version;" <!-- libcilkrts.so.&libcilkrts-version;--> cd /usr/lib @@ -48,24 +58,48 @@ for LIB in $save_usrlib; do rm /tmp/$LIB done -unset LIB save_usrlib</userinput></screen> +online_usrbin="bash find strip" +online_usrlib="libbfd-&binutils-version;.so libdl-&glibc-version;.so + libhistory.so.&readline-version; libncursesw.so.&ncurses-version; + libm-&glibc-version;.so libreadline.so.&readline-version; + libz.so.&zlib-version;" + +for BIN in $online_usrbin; do + cp /usr/bin/$BIN /tmp/$BIN + strip --strip-all /tmp/$BIN + install -vm755 /tmp/$BIN /usr/bin + rm /tmp/$BIN +done -<!-- <para>Before performing the stripping, take special care to ensure that - none of the binaries that are about to be stripped are running:</para> +for LIB in $online_usrlib; do + cp /usr/lib/$LIB /tmp/$LIB + strip --strip-unneeded /tmp/$LIB + install -vm755 /tmp/$LIB /usr/lib + rm /tmp/$LIB +done -<screen role="nodump"><userinput>exec /tools/bin/bash</userinput></screen> - - <para>Now the binaries and libraries can be safely stripped:</para> ---> - <para>Now the binaries and libraries can be stripped:</para> -<screen><userinput>find /usr/lib -type f -name \*.a \ +find /usr/lib -type f -name \*.a \ -exec strip --strip-debug {} ';' -find /usr/lib -type f -name \*.so* ! -name \*dbg ! -name libz.so* \ - -exec strip --strip-unneeded {} ';' +for i in $(find /usr/lib -type f -name \*.so* ! -name \*dbg); do + case "$online_usrlib $save_usrlib" in + *$(basename $i)* ) ;; + * ) strip --strip-unneeded $i ;; + esac +done + +for i in $(find /usr/bin -type f); do + case "$online_usrbin" in + *$(basename $i)* ) ;; + * ) strip --strip-all $i ;; + esac +done + +find /usr/{sbin,libexec} -type f \ + -exec strip --strip-all {} ';' -find /usr/{bin,sbin,libexec} -type f \ - -exec strip --strip-all {} ';'</userinput></screen> +unset BIN LIB save_usrlib online_usrbin online_usrlib +</userinput></screen> <para>A large number of files will be reported as having their file format not recognized. These warnings can be safely ignored. These |