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diff --git a/static/freebsd/man9/memguard.9 3.html b/static/freebsd/man9/memguard.9 3.html deleted file mode 100644 index 8ba31e90..00000000 --- a/static/freebsd/man9/memguard.9 3.html +++ /dev/null @@ -1,135 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">MEMGUARD(9)</td> - <td class="head-vol">Kernel Developer's Manual</td> - <td class="head-rtitle">MEMGUARD(9)</td> - </tr> -</table> -<div class="manual-text"> -<section class="Sh"> -<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> -<p class="Pp"><code class="Nm">MemGuard</code> — <span class="Nd">memory - allocator for debugging purposes</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="Cd">options DEBUG_MEMGUARD</code></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp"><code class="Nm">MemGuard</code> is a simple and small replacement - memory allocator designed to help detect tamper-after-free scenarios. These - problems are more and more common and likely with multithreaded kernels - where race conditions are more prevalent.</p> -<p class="Pp" id="malloc"><code class="Nm">MemGuard</code> can take over - <a class="permalink" href="#malloc"><code class="Fn">malloc</code></a>(), - <a class="permalink" href="#realloc"><code class="Fn" id="realloc">realloc</code></a>() - and - <a class="permalink" href="#free"><code class="Fn" id="free">free</code></a>() - for a single malloc type. Alternatively <code class="Nm">MemGuard</code> can - take over - <a class="permalink" href="#uma_zalloc"><code class="Fn" id="uma_zalloc">uma_zalloc</code></a>(), - <a class="permalink" href="#uma_zalloc_arg"><code class="Fn" id="uma_zalloc_arg">uma_zalloc_arg</code></a>() - and - <a class="permalink" href="#uma_free"><code class="Fn" id="uma_free">uma_free</code></a>() - for a single <a class="Xr">uma(9)</a> zone. Also - <code class="Nm">MemGuard</code> can guard all allocations larger than - <code class="Dv">PAGE_SIZE</code>, and can guard a random fraction of all - allocations. There is also a knob to prevent allocations smaller than a - specified size from being guarded, to limit memory waste.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> -<p class="Pp">To use <code class="Nm">MemGuard</code> for a memory type, either - add an entry to <span class="Pa">/boot/loader.conf</span>:</p> -<div class="Bd Pp Bd-indent Li"> -<pre>vm.memguard.desc=<memory_type></pre> -</div> -<p class="Pp">Or set the <var class="Va">vm.memguard.desc</var> - <a class="Xr">sysctl(8)</a> variable at run-time:</p> -<div class="Bd Pp Bd-indent Li"> -<pre>sysctl vm.memguard.desc=<memory_type></pre> -</div> -<p class="Pp">Where <var class="Ar">memory_type</var> can be either a short - description of the memory type to monitor, either name of - <a class="Xr">uma(9)</a> zone. Only allocations from that - <var class="Ar">memory_type</var> made after - <var class="Va">vm.memguard.desc</var> is set will potentially be guarded. - If <var class="Va">vm.memguard.desc</var> is modified at run-time then only - allocations of the new <var class="Ar">memory_type</var> will potentially be - guarded once the <a class="Xr">sysctl(8)</a> is set. Existing guarded - allocations will still be properly released by either - <a class="Xr">free(9)</a> or <a class="Xr">uma_zfree(9)</a>, depending on - what kind of allocation was taken over.</p> -<p class="Pp">To determine short description of a <a class="Xr">malloc(9)</a> - type one can either take it from the first column of - <a class="Xr">vmstat(8)</a> <code class="Fl">-m</code> output, or to find it - in the kernel source. It is the second argument to - <a class="Xr">MALLOC_DEFINE(9)</a> macro. To determine name of - <a class="Xr">uma(9)</a> zone one can either take it from the first column - of <a class="Xr">vmstat(8)</a> <code class="Fl">-z</code> output, or to find - it in the kernel source. It is the first argument to the - <a class="Xr">uma_zcreate(9)</a> function.</p> -<p class="Pp">The <var class="Va">vm.memguard.divisor</var> boot-time tunable is - used to scale how much of the system's physical memory - <code class="Nm">MemGuard</code> is allowed to consume. The default is 10, - so up to <var class="Va">vm_cnt.v_page_count</var>/10 pages can be used. - <code class="Nm">MemGuard</code> will reserve - <var class="Va">vm_kmem_max</var> / - <var class="Va">vm.memguard.divisor</var> bytes of virtual address space, - limited by twice the physical memory size. The physical limit is reported as - <var class="Va">vm.memguard.phys_limit</var> and the virtual space reserved - for <code class="Nm">MemGuard</code> is reported as - <var class="Va">vm.memguard.mapsize</var>.</p> -<p class="Pp"><code class="Nm">MemGuard</code> will not do page promotions for - any allocation smaller than <var class="Va">vm.memguard.minsize</var> bytes. - The default is 0, meaning all allocations can potentially be guarded. - <code class="Nm">MemGuard</code> can guard sufficiently large allocations - randomly, with average frequency of every one in 100000 / - <var class="Va">vm.memguard.frequency</var> allocations. The default is 0, - meaning no allocations are randomly guarded.</p> -<p class="Pp"><code class="Nm">MemGuard</code> can optionally add unmapped guard - pages around each allocation to detect overflow and underflow, if - <var class="Va">vm.memguard.options</var> has the 1 bit set. This option is - enabled by default. <code class="Nm">MemGuard</code> will optionally guard - all allocations of <code class="Dv">PAGE_SIZE</code> or larger if - <var class="Va">vm.memguard.options</var> has the 2 bit set. This option is - off by default. By default <code class="Nm">MemGuard</code> does not guard - <a class="Xr">uma(9)</a> zones that have been initialized with the - <code class="Dv">UMA_ZONE_NOFREE</code> flag set, since it can produce false - positives on them. However, this safety measure can be turned off by setting - bit 3 of the <var class="Va">vm.memguard.options</var> tunable.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE - ALSO</a></h1> -<p class="Pp"><a class="Xr">sysctl(8)</a>, <a class="Xr">vmstat(8)</a>, - <a class="Xr">contigmalloc(9)</a>, <a class="Xr">malloc(9)</a>, - <a class="Xr">redzone(9)</a>, <a class="Xr">uma(9)</a></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp"><code class="Nm">MemGuard</code> first appeared in - <span class="Ux">FreeBSD 6.0</span>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> -<p class="Pp"><code class="Nm">MemGuard</code> was originally written by - <span class="An">Bosko Milekic</span> - <<a class="Mt" href="mailto:bmilekic@FreeBSD.org">bmilekic@FreeBSD.org</a>>. - This manual page was originally written by <span class="An">Christian - Brueffer</span> - <<a class="Mt" href="mailto:brueffer@FreeBSD.org">brueffer@FreeBSD.org</a>>. - Additions have been made by <span class="An">Matthew Fleming</span> - <<a class="Mt" href="mailto:mdf@FreeBSD.org">mdf@FreeBSD.org</a>> and - <span class="An">Gleb Smirnoff</span> - <<a class="Mt" href="mailto:glebius@FreeBSD.org">glebius@FreeBSD.org</a>> - to both the implementation and the documentation.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">March 22, 2017</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |